Re: [Elecraft] Silent power supply for a K3s
Easy way out of this mess, if a little expensive... A big PSU dedicated to the rig(s), implementing "Remote Sensing" so at a distribution point close to the radio(s) the DC voltage is held constant, irrespective of the cable length from the PSU. This power supply should have a proper overload (and over voltage) protection scheme too, not only to protect itself, but the radio(s) also. And safety resistors between + and +s, also between - and -s terminals. (Prevents expensive embarrassment, if a sense line fails!) Then use a smaller PSU for the low power accessories, with suitable fusing. Any QRO power amp, needing really high current, should have it's own independent dedicated PSU, again with remote sensing to keep the voltage at the PA as near constant as it can be, and the resulting high DC currents, purely between the PA and it's PSU. Just my way of doing things, to keep the high DC currents out of the RF cabling. Google "power supply remote sensing" for more info. 73. Dave G0WBX. -- Created on and sent from a Unix like PC running and using free and open source software: __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
On 2019-06-12 7:55 PM, Don Wilhelm wrote: Connection resistance contributes .05 volt loss under a 20 amp load for each contact point, you have 6 contact points in the path for a fused RigRunner plus two in the APP connector at the transceiver, plus the connection to the power supply for a total of 10 contact points. You have to consider the negative path as well as the positive. So that is a total of 0.5 volts of the total voltage drop. This assumes the APP connections into and out of the RigRunner are assembled correctly (contacts properly aligned). If they are not, the contact resistance will be significantly higher. Further, the 20A current (and the voltage drop I^2*R) may be significantly higher in the cable between the power supply and RigRunner. Again, this will result in *MORE THAN* 0.5 volts of total voltage drop when using a RigRunner type power distribution system. Further, while one may measure 20A in transmit (using the K3 internal "meter") there is a significant time constant, particularly in SSB operation. The actual *peak* current may be closer to 30 - 35A than to 17 - 20A. Since voltage drop in power supply cables and power distribution system are related to the *current squared* the actual *maximum* voltage drop (and loss of voltage regulation, increase in transmit IMD, etc.) will be worse that the static analysis would indicate. 73, ... Joe, W4TV On 2019-06-12 7:55 PM, Don Wilhelm wrote: After consulting copper wire tables and typical connection resistances, I can present the following analysis for a 20 amp load: Often hams power their 100 watt transceivers through DC distribution devices such as a RigRunner which will contribute to the voltage drop. Also in-line fuses will contribute to voltage drop. Connection resistance contributes .05 volt loss under a 20 amp load for each contact point, you have 6 contact points in the path for a fused RigRunner plus two in the APP connector at the transceiver, plus the connection to the power supply for a total of 10 contact points. You have to consider the negative path as well as the positive. So that is a total of 0.5 volts of the total voltage drop. By contrast, a 5 foot length under a 20 amp load of #12 wire has 0.1588 ohms (in both conductors) for a voltage drop of 0.3176 volts, and #10 wire a drop of 0.1998 volts. So conclusion is that while increasing the wire size can reduce the voltage drop, the main contributor is in the power distribution system. A path direct from the power supply terminals can be expected to have a 0.5 volt drop with 5 feet of #12 wire to the inside of the K3. and #10 wire can have a 0.4 volt drop - the difference is only slightly significant. Conclusion - in a 5 foot power cable run, the difference between #10 and #12 wire is only 0.1 volts (0.05 volts in each of the positive and negative leads) - the major contributor is the number of contact points. So for those who choose to measure the voltage drop from the power supply terminals to the APP connector on the outside of the K3, you should measure about 0.2 volts in each conductor with #12 wire and 0.15 volts with #10 wire. If it is much more than that, check your power supply connection tightness and your crimp connections. Run the transceiver direct from a power supply using ring terminals instead of routing through a power distribution accessory. 73, Don W3FPR On 6/12/2019 6:29 PM, Bob McGraw K4TAX wrote: Regarding "heavy gauge wire", I suggest one measure the voltage drop using a DVM connected direct between the power supply Pos terminal and the radio Pos terminal. Likewise do the same for the Neg DC line. Put the radio in CW mode and close the key for rated output. If one finds more than 0.25 volts drop in either the Pos or Neg line, I'd say that attention to the power cable and connectors would be in order. Also measure between radio ground and power supply ground. Again a voltage value greater than 0.25 volts indicates attention to the power distribution system and station equipment grounding is needed. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
After consulting copper wire tables and typical connection resistances, I can present the following analysis for a 20 amp load: Often hams power their 100 watt transceivers through DC distribution devices such as a RigRunner which will contribute to the voltage drop. Also in-line fuses will contribute to voltage drop. Connection resistance contributes .05 volt loss under a 20 amp load for each contact point, you have 6 contact points in the path for a fused RigRunner plus two in the APP connector at the transceiver, plus the connection to the power supply for a total of 10 contact points. You have to consider the negative path as well as the positive. So that is a total of 0.5 volts of the total voltage drop. By contrast, a 5 foot length under a 20 amp load of #12 wire has 0.1588 ohms (in both conductors) for a voltage drop of 0.3176 volts, and #10 wire a drop of 0.1998 volts. So conclusion is that while increasing the wire size can reduce the voltage drop, the main contributor is in the power distribution system. A path direct from the power supply terminals can be expected to have a 0.5 volt drop with 5 feet of #12 wire to the inside of the K3. and #10 wire can have a 0.4 volt drop - the difference is only slightly significant. Conclusion - in a 5 foot power cable run, the difference between #10 and #12 wire is only 0.1 volts (0.05 volts in each of the positive and negative leads) - the major contributor is the number of contact points. So for those who choose to measure the voltage drop from the power supply terminals to the APP connector on the outside of the K3, you should measure about 0.2 volts in each conductor with #12 wire and 0.15 volts with #10 wire. If it is much more than that, check your power supply connection tightness and your crimp connections. Run the transceiver direct from a power supply using ring terminals instead of routing through a power distribution accessory. 73, Don W3FPR On 6/12/2019 6:29 PM, Bob McGraw K4TAX wrote: Regarding "heavy gauge wire", I suggest one measure the voltage drop using a DVM connected direct between the power supply Pos terminal and the radio Pos terminal. Likewise do the same for the Neg DC line. Put the radio in CW mode and close the key for rated output. If one finds more than 0.25 volts drop in either the Pos or Neg line, I'd say that attention to the power cable and connectors would be in order. Also measure between radio ground and power supply ground. Again a voltage value greater than 0.25 volts indicates attention to the power distribution system and station equipment grounding is needed. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
Regarding "heavy gauge wire", I suggest one measure the voltage drop using a DVM connected direct between the power supply Pos terminal and the radio Pos terminal. Likewise do the same for the Neg DC line. Put the radio in CW mode and close the key for rated output. If one finds more than 0.25 volts drop in either the Pos or Neg line, I'd say that attention to the power cable and connectors would be in order. Also measure between radio ground and power supply ground. Again a voltage value greater than 0.25 volts indicates attention to the power distribution system and station equipment grounding is needed. 73 Bob, K4TAX On 6/12/2019 9:17 AM, Harry Yingst via Elecraft wrote: Another vote for the Astron Power Supplies they work well. Use the shortest run between the PS and radio you can and of a heavy gauge wire. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
I also have this power supply and use it frequently for field work. Have had no problems. -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of j...@kk9a.com Sent: Wednesday, June 12, 2019 10:19 AM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] Silent power supply for a K3s I have a Powerwerx SS-30DV power supply but I only use it when operating from the Caribbean. I have not heard any RF noise from it during normal contest operation. I wish that there were more two more PowerPole jacks but I added a junction so I can power all of my 12v peripherals plus the K3S by quickly plugging them in. At home I use a 70amp Astron that I have owned for decades. I have not heard any hum or RFI from it. John KK9A Nate Bargmann N0NB wrote: This is has been an instructive thread as it gives some ideas for quieting the top cover of the RM-50M under my desk. I'm also curious that not much has been written about the Power Werx SS-30DV resold by Elecraft: https://elecraft.com/collections/power-supplies/products/ss30dv-25a-30a-surge-power-supply I presume the engineers at Elecraft have examined this model for noise on the DC output and generated RF noise and found it quiet/acceptable, though a technical report would be nice to see. 73, Nate, N0NB __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to gthorn...@thorntonmostullaw.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
I have a Powerwerx SS-30DV power supply but I only use it when operating from the Caribbean. I have not heard any RF noise from it during normal contest operation. I wish that there were more two more PowerPole jacks but I added a junction so I can power all of my 12v peripherals plus the K3S by quickly plugging them in. At home I use a 70amp Astron that I have owned for decades. I have not heard any hum or RFI from it. John KK9A Nate Bargmann N0NB wrote: This is has been an instructive thread as it gives some ideas for quieting the top cover of the RM-50M under my desk. I'm also curious that not much has been written about the Power Werx SS-30DV resold by Elecraft: https://elecraft.com/collections/power-supplies/products/ss30dv-25a-30a-surge-power-supply I presume the engineers at Elecraft have examined this model for noise on the DC output and generated RF noise and found it quiet/acceptable, though a technical report would be nice to see. 73, Nate, N0NB __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
This is has been an instructive thread as it gives some ideas for quieting the top cover of the RM-50M under my desk. I'm also curious that not much has been written about the Power Werx SS-30DV resold by Elecraft: https://elecraft.com/collections/power-supplies/products/ss30dv-25a-30a-surge-power-supply I presume the engineers at Elecraft have examined this model for noise on the DC output and generated RF noise and found it quiet/acceptable, though a technical report would be nice to see. 73, Nate, N0NB -- "The optimist proclaims that we live in the best of all possible worlds. The pessimist fears this is true." Web: http://www.n0nb.us GPG key: D55A8819 GitHub: N0NB __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
Linear PSs are not noisy as far as I know. You're comparing apples and oranges!! ;-)) Bert VE3NR On 6/12/2019 9:17 AM, Harry Yingst via Elecraft wrote: Another vote for the Astron Power Supplies they work well. Use the shortest run between the PS and radio you can and of a heavy gauge wire. On Tuesday, June 11, 2019, 6:15:14 PM EDT, Bob Nielsen - N7XY wrote: The Astrons are quiet and pretty reliable. I have had a RS20 since 1980 and the only problem I had was cured by replacing the regulator chip about 35 years ago. Bob, N7XY On 6/10/19 5:04 PM, Alan Corbeth wrote: I have an Astron RS35 power Supply purchased in 1991. There was a period where I didn’t use it for ten years. Now it’s in use daily and so far it continues to be totally quiet. Alan K7FH On Jun 10, 2019, at 3:56 AM, Bill wrote: I have several Power Werx switchers and prefer them for their size over the heavy analog supplies. Fans are not a problem (actually, I hear nothing from them at all) - IF you design your radio desk for proper equipment placement. Place the power supply at your right hand - and you WILL hear noise, XFMR, fan, etc. It is amazing what proper station design/construction can do for making silence. Open faced metal shelving and bare desktops don't cut it. Just for grins, I put one of those Nanoxia fans in my IC-7300 and silenced it completely. Worth the few dollars and effort. No temperature changes noted. Hmmm - KPA500? __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to acorb...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to n...@n7xy.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to hlyin...@yahoo.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to ve...@bell.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
I've found a good source for power supply wire for the DC connections. Automotive primary wire, #10 AWG. This wire is made using many small strands which make it very flexible. Various colors are available. I use Red {DC Pos}, Black {DC Neg} and White {equipment bonding wire}. Also I use the proper size for the wire and screw ring terminals {no spade or Y lugs} fitted on each end. I'm and old fashion fellow and and was taught to crimp with the correct crimping tool. I've seen too many hams use the "mash-on" method, thus using what ever tool happens to be in the tool box. A proper crimping tool is designed for the specific connector and sleeve size and does not distort the sleeve. Yea, a good crimping tool may cost you $25 to $35 but it is sure worth it not having to worry about lousy connections. As a test, crimp a lug on a piece of wire. Using pliers, try to pull it off. If you can, it may be the wrong size lug for the wire OR it is not properly crimped. If the wire breaks first, you have a good crimp. 73 Bob, K4TAX On 6/12/2019 8:17 AM, Harry Yingst via Elecraft wrote: Another vote for the Astron Power Supplies they work well. Use the shortest run between the PS and radio you can and of a heavy gauge wire. On Tuesday, June 11, 2019, 6:15:14 PM EDT, Bob Nielsen - N7XY wrote: The Astrons are quiet and pretty reliable. I have had a RS20 since 1980 and the only problem I had was cured by replacing the regulator chip about 35 years ago. Bob, N7XY On 6/10/19 5:04 PM, Alan Corbeth wrote: I have an Astron RS35 power Supply purchased in 1991. There was a period where I didn’t use it for ten years. Now it’s in use daily and so far it continues to be totally quiet. Alan K7FH On Jun 10, 2019, at 3:56 AM, Bill wrote: I have several Power Werx switchers and prefer them for their size over the heavy analog supplies. Fans are not a problem (actually, I hear nothing from them at all) - IF you design your radio desk for proper equipment placement. Place the power supply at your right hand - and you WILL hear noise, XFMR, fan, etc. It is amazing what proper station design/construction can do for making silence. Open faced metal shelving and bare desktops don't cut it. Just for grins, I put one of those Nanoxia fans in my IC-7300 and silenced it completely. Worth the few dollars and effort. No temperature changes noted. Hmmm - KPA500? __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to acorb...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to n...@n7xy.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to hlyin...@yahoo.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to rmcg...@blomand.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
Another vote for the Astron Power Supplies they work well. Use the shortest run between the PS and radio you can and of a heavy gauge wire. On Tuesday, June 11, 2019, 6:15:14 PM EDT, Bob Nielsen - N7XY wrote: The Astrons are quiet and pretty reliable. I have had a RS20 since 1980 and the only problem I had was cured by replacing the regulator chip about 35 years ago. Bob, N7XY On 6/10/19 5:04 PM, Alan Corbeth wrote: > I have an Astron RS35 power Supply purchased in 1991. There was a period > where I didn’t use it for ten years. Now it’s in use daily and so far it > continues to be totally quiet. > > Alan > K7FH > >> On Jun 10, 2019, at 3:56 AM, Bill wrote: >> >> I have several Power Werx switchers and prefer them for their size over the >> heavy analog supplies. Fans are not a problem (actually, I hear nothing from >> them at all) - IF you design your radio desk for proper equipment placement. >> Place the power supply at your right hand - and you WILL hear noise, XFMR, >> fan, etc. >> >> It is amazing what proper station design/construction can do for making >> silence. Open faced metal shelving and bare desktops don't cut it. >> >> Just for grins, I put one of those Nanoxia fans in my IC-7300 and silenced >> it completely. Worth the few dollars and effort. No temperature changes >> noted. Hmmm - KPA500? >> >> >> __ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> Message delivered to acorb...@gmail.com > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to n...@n7xy.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to hlyin...@yahoo.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
The Astrons are quiet and pretty reliable. I have had a RS20 since 1980 and the only problem I had was cured by replacing the regulator chip about 35 years ago. Bob, N7XY On 6/10/19 5:04 PM, Alan Corbeth wrote: I have an Astron RS35 power Supply purchased in 1991. There was a period where I didn’t use it for ten years. Now it’s in use daily and so far it continues to be totally quiet. Alan K7FH On Jun 10, 2019, at 3:56 AM, Bill wrote: I have several Power Werx switchers and prefer them for their size over the heavy analog supplies. Fans are not a problem (actually, I hear nothing from them at all) - IF you design your radio desk for proper equipment placement. Place the power supply at your right hand - and you WILL hear noise, XFMR, fan, etc. It is amazing what proper station design/construction can do for making silence. Open faced metal shelving and bare desktops don't cut it. Just for grins, I put one of those Nanoxia fans in my IC-7300 and silenced it completely. Worth the few dollars and effort. No temperature changes noted. Hmmm - KPA500? __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to acorb...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to n...@n7xy.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
I have twelve RS-35M power supplies and all are completely quiet. - Original Message - From: "Alan Corbeth" To: "Bill" Cc: "Elecraft International Group" Sent: Tuesday, June 11, 2019 12:04:02 AM Subject: Re: [Elecraft] Silent power supply for a K3s I have an Astron RS35 power Supply purchased in 1991. There was a period where I didn’t use it for ten years. Now it’s in use daily and so far it continues to be totally quiet. Alan K7FH > On Jun 10, 2019, at 3:56 AM, Bill wrote: > > I have several Power Werx switchers and prefer them for their size over the > heavy analog supplies. Fans are not a problem (actually, I hear nothing from > them at all) - IF you design your radio desk for proper equipment placement. > Place the power supply at your right hand - and you WILL hear noise, XFMR, > fan, etc. > > It is amazing what proper station design/construction can do for making > silence. Open faced metal shelving and bare desktops don't cut it. > > Just for grins, I put one of those Nanoxia fans in my IC-7300 and silenced it > completely. Worth the few dollars and effort. No temperature changes noted. > Hmmm - KPA500? > > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to acorb...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to donov...@starpower.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
I have an Astron RS35 power Supply purchased in 1991. There was a period where I didn’t use it for ten years. Now it’s in use daily and so far it continues to be totally quiet. Alan K7FH > On Jun 10, 2019, at 3:56 AM, Bill wrote: > > I have several Power Werx switchers and prefer them for their size over the > heavy analog supplies. Fans are not a problem (actually, I hear nothing from > them at all) - IF you design your radio desk for proper equipment placement. > Place the power supply at your right hand - and you WILL hear noise, XFMR, > fan, etc. > > It is amazing what proper station design/construction can do for making > silence. Open faced metal shelving and bare desktops don't cut it. > > Just for grins, I put one of those Nanoxia fans in my IC-7300 and silenced it > completely. Worth the few dollars and effort. No temperature changes noted. > Hmmm - KPA500? > > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to acorb...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
candy cookies,,,bottle of wine Bob On Mon, 10 Jun 2019 00:16:10 -0400 Bert writes: > How would a switched PS take out a radio? > > Bert VE3NR > > > > On 6/9/2019 11:40 PM, Jim - N4ST wrote: > > I don't know how common it is, but eHam lists several failures of > the > > MFJ-4230MV supply that took out the rig attached to it. > > Looking at the reviews they are pretty much a 5 (love it) or a 0 > (it smoked > > my rig when it failed). > > > > > > 73, > > Jim - N4ST > > > > > > -Original Message- > > From: elecraft-boun...@mailman.qth.net > On > > Behalf Of Richard Zalewski > > Sent: Sunday, June 9, 2019 19:53 > > To: Leroy Buller > > Cc: Elecraft Reflector > > Subject: Re: [Elecraft] Silent power supply for a K3s > > > > I did two of the Samlex and returned them both. The fan problem > drove me > > crazy. I replaced it with a MFJ-4230MV and love it. Quiet cool > and good > > metering. > > > > Richard > > *W7ZR* ex:5C5Z, CN2ZR, K2JSP, W6SBZ, W7KXR, K9ZIJ, W9KNF, W0KDF, > W0MQU, > > J68ZR, KC6ZR, PJ4/W7ZR, KH2,W7ZR, KH6/W7ZR, V31ZR, VK4AAZ, XE2DV > > > > > > *Be joyful in hope, patient in affliction, faithful in prayer* > > > > __ > > Elecraft mailing list > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/mmfaq.htm > > Post: mailto:Elecraft@mailman.qth.net > > > > This list hosted by: http://www.qsl.net > > Please help support this email list: > http://www.qsl.net/donate.html > > Message delivered to ve...@bell.net > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to riese-k3...@juno.com > __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
Astron has an Over-Voltage protection option that is an add-on accessory. In the past it was an option or included on some models. If the regulation series transistor shorts or the regulation circuits malfunctions, then the over-voltage protection shorts the output and blows the fuse(s). My present RS-35M included it in the purchase. Since the late 70s or early 80s, I have used various current rated Astrons in both 12 and 24 volts with few if any issues except when Florida Flash & Flicker passed an EMP or such down the line! BTW - Never have heard it and it is well over 10 years old. George AI4VZ -Original Message- From: Charlie T Sent: Monday, June 10, 2019 7:57 AM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] Silent power supply for a K3s Any supply that is regulated, whether a switching or linear regulator circuit is used, has the potential to "take-out" the radio because if the regulating circuit fails, the un-regulated voltage which is normally significantly higher than the regulated voltage will be applied to the radio. In a 12 - 14 V supply, this could very well damage anything it is connected to, from a simple 12V light bulb to your fancy new SS radio. That said, many good quality commercial power supplies have what is called a "crow-bar" circuit which is essentially a big SCR across the supply's output, with its gate driven by a voltage sensing circuit set a level slightly higher than the supply's normal output, say 16V. The action is if the regulator fails, the sensing circuit fires the SCR, which is hopefully big enough to effectively short the power supply's output and ether trigger a fold-back current limiting * circuit, or blow a fuse. 73, Charlie k3ICH *Unfortunately, in many supplies, the current limiter AND voltage regulator use the same active device, so in a fault situation, blowing the fuse is the last resort to a safe shut down. -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Bert Sent: Monday, June 10, 2019 12:16 AM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] Silent power supply for a K3s How would a switched PS take out a radio? Bert VE3NR On 6/9/2019 11:40 PM, Jim - N4ST wrote: > I don't know how common it is, but eHam lists several failures of the > MFJ-4230MV supply that took out the rig attached to it. > Looking at the reviews they are pretty much a 5 (love it) or a 0 (it > smoked my rig when it failed). > > > 73, > Jim - N4ST > > > -Original Message- > From: elecraft-boun...@mailman.qth.net > On Behalf Of Richard Zalewski > Sent: Sunday, June 9, 2019 19:53 > To: Leroy Buller > Cc: Elecraft Reflector > Subject: Re: [Elecraft] Silent power supply for a K3s > > I did two of the Samlex and returned them both. The fan problem drove > me crazy. I replaced it with a MFJ-4230MV and love it. Quiet cool > and good metering. > > Richard > *W7ZR* ex:5C5Z, CN2ZR, K2JSP, W6SBZ, W7KXR, K9ZIJ, W9KNF, W0KDF, > W0MQU, J68ZR, KC6ZR, PJ4/W7ZR, KH2,W7ZR, KH6/W7ZR, V31ZR, VK4AAZ, > XE2DV > > > *Be joyful in hope, patient in affliction, faithful in prayer* > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net Please help support this email > list: http://www.qsl.net/donate.html Message delivered to > ve...@bell.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to pin...@erols.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to gdanne...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
On 6/9/2019 23:16, Bert wrote: How would a switched PS take out a radio? Bert VE3NR Most likely due to overvoltage. Linear supplies are particularly susceptible, as the series pass transistor is under stress and can short. Switching supplies can fail if the voltage feedback loop somehow opens up. I've not heard of it happening, but all it would take would be one failed resistor or solder joint. I use a switching supply for my K3, but I built an external overvoltage protector. Of course, the supply has never failed. BTW, I've found that the fan noise from the Samlex SEC-1235 is never audible above the K3 fans, except during long periods of receive, when the low speed supply fan is just barely audible. (I did the mod, so the supply fan runs at low speed all the time.) If I transmit long enough for the supply fan to switch to full speed, the K3 fans are already running fast enough to drown it out. Not to mention those in the KPA-1500. I'm very happy with the Samlex supply. I've never detected a trace of RFI from it. 73, Scott K9MA -- Scott K9MA k...@sdellington.us __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
Any supply that is regulated, whether a switching or linear regulator circuit is used, has the potential to "take-out" the radio because if the regulating circuit fails, the un-regulated voltage which is normally significantly higher than the regulated voltage will be applied to the radio. In a 12 - 14 V supply, this could very well damage anything it is connected to, from a simple 12V light bulb to your fancy new SS radio. That said, many good quality commercial power supplies have what is called a "crow-bar" circuit which is essentially a big SCR across the supply's output, with its gate driven by a voltage sensing circuit set a level slightly higher than the supply's normal output, say 16V. The action is if the regulator fails, the sensing circuit fires the SCR, which is hopefully big enough to effectively short the power supply's output and ether trigger a fold-back current limiting * circuit, or blow a fuse. 73, Charlie k3ICH *Unfortunately, in many supplies, the current limiter AND voltage regulator use the same active device, so in a fault situation, blowing the fuse is the last resort to a safe shut down. -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Bert Sent: Monday, June 10, 2019 12:16 AM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] Silent power supply for a K3s How would a switched PS take out a radio? Bert VE3NR On 6/9/2019 11:40 PM, Jim - N4ST wrote: > I don't know how common it is, but eHam lists several failures of the > MFJ-4230MV supply that took out the rig attached to it. > Looking at the reviews they are pretty much a 5 (love it) or a 0 (it > smoked my rig when it failed). > > > 73, > Jim - N4ST > > > -Original Message- > From: elecraft-boun...@mailman.qth.net > On Behalf Of Richard Zalewski > Sent: Sunday, June 9, 2019 19:53 > To: Leroy Buller > Cc: Elecraft Reflector > Subject: Re: [Elecraft] Silent power supply for a K3s > > I did two of the Samlex and returned them both. The fan problem drove > me crazy. I replaced it with a MFJ-4230MV and love it. Quiet cool > and good metering. > > Richard > *W7ZR* ex:5C5Z, CN2ZR, K2JSP, W6SBZ, W7KXR, K9ZIJ, W9KNF, W0KDF, > W0MQU, J68ZR, KC6ZR, PJ4/W7ZR, KH2,W7ZR, KH6/W7ZR, V31ZR, VK4AAZ, > XE2DV > > > *Be joyful in hope, patient in affliction, faithful in prayer* > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net Please help support this email > list: http://www.qsl.net/donate.html Message delivered to > ve...@bell.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to pin...@erols.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
I think that's probably going to be the winner for me if it is indeed silent (or near-silent). Thanks Bob! - pjd -Original Message- From: Bob McGraw K4TAX Sent: Sunday, June 9, 2019 1:57 PM To: Peter Dougherty Cc: Elecraft@mailman.qth.net Subject: Re: [Elecraft] Silent power supply for a K3s I'm using an Astron SS-30M with very satisfactory results. 73 Bob, K4TAX __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
I have several Power Werx switchers and prefer them for their size over the heavy analog supplies. Fans are not a problem (actually, I hear nothing from them at all) - IF you design your radio desk for proper equipment placement. Place the power supply at your right hand - and you WILL hear noise, XFMR, fan, etc. It is amazing what proper station design/construction can do for making silence. Open faced metal shelving and bare desktops don't cut it. Just for grins, I put one of those Nanoxia fans in my IC-7300 and silenced it completely. Worth the few dollars and effort. No temperature changes noted. Hmmm - KPA500? __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
Somewhere around 1980 I was talked into buying a power supply at a hamfest by my good friend who was a great technician. He told me it was a terrific deal. He was right. I don't remember what I paid for it but I know it was lessthan $100. It was a 56 amp rack mounted Llamda metered supply. The model is an LM G12-M. I believe it weighs about 75 pounds. I used to have it in a relay rack at my old QTH shack. In my present shack I have it sitting on a furnituredolly which makes it easy to roll around on the floor. It sits under my desk. It developed an audible arc when turned on so I leave it on 24 - 7. I'm sure the new cost of it would be pretty high but I'm so glad I followed my friend's advice tobuy it. No RFI and no fans. BillK3WJV On Sunday, June 9, 2019, 4:30:07 PM EDT, Ken Winterling wrote: I use an IOTA DLS-55 SMPS power supply (https://www.iotaengineering.com/ dls55.htm). It provides 55 amps, doesn’t produce RFI, is audibly quiet, and rugged. Mine is mounted under the radio table and is on 24/7/365.. I never hear it. Iota also makes them in other output currents and voltages. Ken WA2LBI On Sun, Jun 9, 2019 at 3:27 PM Bob McGraw K4TAX wrote: > I find Mark's point very important. Obtain and use a supply which is > more than adequate for the service or load. Thus a 25 amp supply > feeding a radio drawing 20+ amps will need lots of cooling. This is > not the way to do it. Get a 50 amp supply for a radio drawing 20+ amps > and the fan(s) will likely never come on. Go the cheap way and get > the cheap results. Do it right and be happy. Don't be a cheap ham > and then complain about the product you purchased. > > There is more to choosing a power supply than volts and amps. How about > duty cycle? And CCS rated supplies vs. ICAS rated supplies. Humm... > > 73 > > Bob, K4TAX > > > On 6/9/2019 2:12 PM, Mark Murray via Elecraft wrote: > > Peter, > > > > Check out the high amperage 13,8 volt power supplies offered by Samlex > > America at the following link, and in particular their 100-amp -plus > > (continuous) supplies where the fans do not activate for low draws. You > had > > mentioned something about price not being so important. These ain't > cheap. > > 73 de Mark .w2or. > > > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to wa2...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to k3...@yahoo.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
How would a switched PS take out a radio? Bert VE3NR On 6/9/2019 11:40 PM, Jim - N4ST wrote: I don't know how common it is, but eHam lists several failures of the MFJ-4230MV supply that took out the rig attached to it. Looking at the reviews they are pretty much a 5 (love it) or a 0 (it smoked my rig when it failed). 73, Jim - N4ST -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Richard Zalewski Sent: Sunday, June 9, 2019 19:53 To: Leroy Buller Cc: Elecraft Reflector Subject: Re: [Elecraft] Silent power supply for a K3s I did two of the Samlex and returned them both. The fan problem drove me crazy. I replaced it with a MFJ-4230MV and love it. Quiet cool and good metering. Richard *W7ZR* ex:5C5Z, CN2ZR, K2JSP, W6SBZ, W7KXR, K9ZIJ, W9KNF, W0KDF, W0MQU, J68ZR, KC6ZR, PJ4/W7ZR, KH2,W7ZR, KH6/W7ZR, V31ZR, VK4AAZ, XE2DV *Be joyful in hope, patient in affliction, faithful in prayer* __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to ve...@bell.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
I don't know how common it is, but eHam lists several failures of the MFJ-4230MV supply that took out the rig attached to it. Looking at the reviews they are pretty much a 5 (love it) or a 0 (it smoked my rig when it failed). 73, Jim - N4ST -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Richard Zalewski Sent: Sunday, June 9, 2019 19:53 To: Leroy Buller Cc: Elecraft Reflector Subject: Re: [Elecraft] Silent power supply for a K3s I did two of the Samlex and returned them both. The fan problem drove me crazy. I replaced it with a MFJ-4230MV and love it. Quiet cool and good metering. Richard *W7ZR* ex:5C5Z, CN2ZR, K2JSP, W6SBZ, W7KXR, K9ZIJ, W9KNF, W0KDF, W0MQU, J68ZR, KC6ZR, PJ4/W7ZR, KH2,W7ZR, KH6/W7ZR, V31ZR, VK4AAZ, XE2DV *Be joyful in hope, patient in affliction, faithful in prayer* __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
How old was the RS35 before it started to buzz? Could this be as simple as buying another RS35? Mike va3mw On Sun, Jun 9, 2019 at 7:54 PM Richard Zalewski wrote: > I did two of the Samlex and returned them both. The fan problem drove me > crazy. I replaced it with a MFJ-4230MV and love it. Quiet cool and good > metering. > > Richard > *W7ZR* ex:5C5Z, CN2ZR, K2JSP, W6SBZ, W7KXR, K9ZIJ, W9KNF, W0KDF, W0MQU, > J68ZR, KC6ZR, PJ4/W7ZR, KH2,W7ZR, KH6/W7ZR, V31ZR, VK4AAZ, XE2DV > > > *Be joyful in hope, patient in affliction, faithful in prayer* > > > On Sun, Jun 9, 2019 at 4:39 PM Leroy Buller wrote: > > > As alway...way cool. > > > > Lee K0WA > > > > On Sun, Jun 9, 2019, 6:16 PM Jim Brown > wrote: > > > > > On 6/9/2019 7:52 AM, Peter Dougherty wrote: > > > > Any suggestions? Within reason, cost isn't a > > > > major issue. > > > > > > Sure. Another linear Astron, maybe bigger, higher power rated. I don't > > > know how common the buzzing problem is. As Lee suggested, tighten > screws > > > and bolts on the one you have if you still have it. > > > > > > Another important thing with Astrons is to fix their bonding problem, > as > > > described in this link. > > > http://k9yc.com/PowerSupplyBondingAndAudioDistortion.pdf > > > > > > BTW -- I still do the big float-charged battery thing, but it's now a > > > 100Ah Bioenne Power LiFePO4, and the charger is a spare power supply > for > > > one of my Thinkpads, using a Genasun solar charge controller. That's > > > not an inexpensive solution, but it IS a very good UPS for the radios, > > > AND the supply voltage stays above 13.2V under load as measured within > > > the K3, there's less IMD on TX. The Genasun controller is RF quiet, and > > > allows the Thinkpad PSU to charge the battery at about 7.5A. Make sure > > > that you buy the 14.2V version for LiFePO4 chemistry. > > > > > > > > > > > > https://www.amazon.com/Genasun-GV-10-Li-14-2V-Controller-Lithium-Batteries/dp/B01N6AXQZH/ref=asc_df_B01N6AXQZH/?tag=hyprod-20&linkCode=df0&hvadid=198068984819&hvpos=1o4&hvnetw=g&hvrand=17014603795544971507&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9032155&hvtargid=pla-354296381972&psc=1 > > > > > > I use a separate sealed lead-acid battery to run the other 12V stuff, > > > which includes antenna switching relays, LED lighting, three LCD > > > monitors, and several accessories. It's charged by another Thinkpad PSU > > > with a lead-acid version of the same Genasun controller. I do, of > > > course, have multi-turn ferrite chokes on the chargers and on the LCD > > > monitor power and video lines. > > > > > > For about half of my contesting, my K3s run at about 50W driving an 87A > > > or 25W driving a KPA500, and this DC power arrangement has no trouble > > > keeping up. > > > > > > 73, Jim K9YC > > > > > > __ > > > Elecraft mailing list > > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > > Help: http://mailman.qth.net/mmfaq.htm > > > Post: mailto:Elecraft@mailman.qth.net > > > > > > This list hosted by: http://www.qsl.net > > > Please help support this email list: http://www.qsl.net/donate.html > > > Message delivered to lee.bul...@gmail.com > > __ > > Elecraft mailing list > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/mmfaq.htm > > Post: mailto:Elecraft@mailman.qth.net > > > > This list hosted by: http://www.qsl.net > > Please help support this email list: http://www.qsl.net/donate.html > > Message delivered to dick.w...@gmail.com > > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to va...@portcredit.net > __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
I did two of the Samlex and returned them both. The fan problem drove me crazy. I replaced it with a MFJ-4230MV and love it. Quiet cool and good metering. Richard *W7ZR* ex:5C5Z, CN2ZR, K2JSP, W6SBZ, W7KXR, K9ZIJ, W9KNF, W0KDF, W0MQU, J68ZR, KC6ZR, PJ4/W7ZR, KH2,W7ZR, KH6/W7ZR, V31ZR, VK4AAZ, XE2DV *Be joyful in hope, patient in affliction, faithful in prayer* On Sun, Jun 9, 2019 at 4:39 PM Leroy Buller wrote: > As alway...way cool. > > Lee K0WA > > On Sun, Jun 9, 2019, 6:16 PM Jim Brown wrote: > > > On 6/9/2019 7:52 AM, Peter Dougherty wrote: > > > Any suggestions? Within reason, cost isn't a > > > major issue. > > > > Sure. Another linear Astron, maybe bigger, higher power rated. I don't > > know how common the buzzing problem is. As Lee suggested, tighten screws > > and bolts on the one you have if you still have it. > > > > Another important thing with Astrons is to fix their bonding problem, as > > described in this link. > > http://k9yc.com/PowerSupplyBondingAndAudioDistortion.pdf > > > > BTW -- I still do the big float-charged battery thing, but it's now a > > 100Ah Bioenne Power LiFePO4, and the charger is a spare power supply for > > one of my Thinkpads, using a Genasun solar charge controller. That's > > not an inexpensive solution, but it IS a very good UPS for the radios, > > AND the supply voltage stays above 13.2V under load as measured within > > the K3, there's less IMD on TX. The Genasun controller is RF quiet, and > > allows the Thinkpad PSU to charge the battery at about 7.5A. Make sure > > that you buy the 14.2V version for LiFePO4 chemistry. > > > > > > > https://www.amazon.com/Genasun-GV-10-Li-14-2V-Controller-Lithium-Batteries/dp/B01N6AXQZH/ref=asc_df_B01N6AXQZH/?tag=hyprod-20&linkCode=df0&hvadid=198068984819&hvpos=1o4&hvnetw=g&hvrand=17014603795544971507&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9032155&hvtargid=pla-354296381972&psc=1 > > > > I use a separate sealed lead-acid battery to run the other 12V stuff, > > which includes antenna switching relays, LED lighting, three LCD > > monitors, and several accessories. It's charged by another Thinkpad PSU > > with a lead-acid version of the same Genasun controller. I do, of > > course, have multi-turn ferrite chokes on the chargers and on the LCD > > monitor power and video lines. > > > > For about half of my contesting, my K3s run at about 50W driving an 87A > > or 25W driving a KPA500, and this DC power arrangement has no trouble > > keeping up. > > > > 73, Jim K9YC > > > > __ > > Elecraft mailing list > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/mmfaq.htm > > Post: mailto:Elecraft@mailman.qth.net > > > > This list hosted by: http://www.qsl.net > > Please help support this email list: http://www.qsl.net/donate.html > > Message delivered to lee.bul...@gmail.com > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to dick.w...@gmail.com > __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
The issue with oversizing it is (for the energy conscious) a linear supply demands more, ALL the time (it's inefficient with energy). In some places it matters because of the KwH costs. pennies turn into dollars. (Not here, I was used to the higher prices and after I moved here, I just stopped caring because the costs were 1/3 or less. I've even been known to run the air conditioner here!) Rick nhc On 6/9/2019 12:26 PM, Bob McGraw K4TAX wrote: I find Mark's point very important. Obtain and use a supply which is more than adequate for the service or load. Thus a 25 amp supply feeding a radio drawing 20+ amps will need lots of cooling. This is not the way to do it. Get a 50 amp supply for a radio drawing 20+ amps and the fan(s) will likely never come on. Go the cheap way and get the cheap results. Do it right and be happy. Don't be a cheap ham and then complain about the product you purchased. There is more to choosing a power supply than volts and amps. How about duty cycle? And CCS rated supplies vs. ICAS rated supplies. Humm... 73 Bob, K4TAX On 6/9/2019 2:12 PM, Mark Murray via Elecraft wrote: Peter, Check out the high amperage 13,8 volt power supplies offered by Samlex America at the following link, and in particular their 100-amp -plus (continuous) supplies where the fans do not activate for low draws. You had mentioned something about price not being so important. These ain't cheap. 73 de Mark .w2or. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to wa6...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
As alway...way cool. Lee K0WA On Sun, Jun 9, 2019, 6:16 PM Jim Brown wrote: > On 6/9/2019 7:52 AM, Peter Dougherty wrote: > > Any suggestions? Within reason, cost isn't a > > major issue. > > Sure. Another linear Astron, maybe bigger, higher power rated. I don't > know how common the buzzing problem is. As Lee suggested, tighten screws > and bolts on the one you have if you still have it. > > Another important thing with Astrons is to fix their bonding problem, as > described in this link. > http://k9yc.com/PowerSupplyBondingAndAudioDistortion.pdf > > BTW -- I still do the big float-charged battery thing, but it's now a > 100Ah Bioenne Power LiFePO4, and the charger is a spare power supply for > one of my Thinkpads, using a Genasun solar charge controller. That's > not an inexpensive solution, but it IS a very good UPS for the radios, > AND the supply voltage stays above 13.2V under load as measured within > the K3, there's less IMD on TX. The Genasun controller is RF quiet, and > allows the Thinkpad PSU to charge the battery at about 7.5A. Make sure > that you buy the 14.2V version for LiFePO4 chemistry. > > > https://www.amazon.com/Genasun-GV-10-Li-14-2V-Controller-Lithium-Batteries/dp/B01N6AXQZH/ref=asc_df_B01N6AXQZH/?tag=hyprod-20&linkCode=df0&hvadid=198068984819&hvpos=1o4&hvnetw=g&hvrand=17014603795544971507&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9032155&hvtargid=pla-354296381972&psc=1 > > I use a separate sealed lead-acid battery to run the other 12V stuff, > which includes antenna switching relays, LED lighting, three LCD > monitors, and several accessories. It's charged by another Thinkpad PSU > with a lead-acid version of the same Genasun controller. I do, of > course, have multi-turn ferrite chokes on the chargers and on the LCD > monitor power and video lines. > > For about half of my contesting, my K3s run at about 50W driving an 87A > or 25W driving a KPA500, and this DC power arrangement has no trouble > keeping up. > > 73, Jim K9YC > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to lee.bul...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
On 6/9/2019 7:52 AM, Peter Dougherty wrote: Any suggestions? Within reason, cost isn't a major issue. Sure. Another linear Astron, maybe bigger, higher power rated. I don't know how common the buzzing problem is. As Lee suggested, tighten screws and bolts on the one you have if you still have it. Another important thing with Astrons is to fix their bonding problem, as described in this link. http://k9yc.com/PowerSupplyBondingAndAudioDistortion.pdf BTW -- I still do the big float-charged battery thing, but it's now a 100Ah Bioenne Power LiFePO4, and the charger is a spare power supply for one of my Thinkpads, using a Genasun solar charge controller. That's not an inexpensive solution, but it IS a very good UPS for the radios, AND the supply voltage stays above 13.2V under load as measured within the K3, there's less IMD on TX. The Genasun controller is RF quiet, and allows the Thinkpad PSU to charge the battery at about 7.5A. Make sure that you buy the 14.2V version for LiFePO4 chemistry. https://www.amazon.com/Genasun-GV-10-Li-14-2V-Controller-Lithium-Batteries/dp/B01N6AXQZH/ref=asc_df_B01N6AXQZH/?tag=hyprod-20&linkCode=df0&hvadid=198068984819&hvpos=1o4&hvnetw=g&hvrand=17014603795544971507&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9032155&hvtargid=pla-354296381972&psc=1 I use a separate sealed lead-acid battery to run the other 12V stuff, which includes antenna switching relays, LED lighting, three LCD monitors, and several accessories. It's charged by another Thinkpad PSU with a lead-acid version of the same Genasun controller. I do, of course, have multi-turn ferrite chokes on the chargers and on the LCD monitor power and video lines. For about half of my contesting, my K3s run at about 50W driving an 87A or 25W driving a KPA500, and this DC power arrangement has no trouble keeping up. 73, Jim K9YC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
I use an IOTA DLS-55 SMPS power supply (https://www.iotaengineering.com/ dls55.htm). It provides 55 amps, doesn’t produce RFI, is audibly quiet, and rugged. Mine is mounted under the radio table and is on 24/7/365.. I never hear it. Iota also makes them in other output currents and voltages. Ken WA2LBI On Sun, Jun 9, 2019 at 3:27 PM Bob McGraw K4TAX wrote: > I find Mark's point very important. Obtain and use a supply which is > more than adequate for the service or load. Thus a 25 amp supply > feeding a radio drawing 20+ amps will need lots of cooling. This is > not the way to do it. Get a 50 amp supply for a radio drawing 20+ amps > and the fan(s) will likely never come on. Go the cheap way and get > the cheap results.Do it right and be happy. Don't be a cheap ham > and then complain about the product you purchased. > > There is more to choosing a power supply than volts and amps. How about > duty cycle? And CCS rated supplies vs. ICAS rated supplies. Humm... > > 73 > > Bob, K4TAX > > > On 6/9/2019 2:12 PM, Mark Murray via Elecraft wrote: > > Peter, > > > > Check out the high amperage 13,8 volt power supplies offered by Samlex > > America at the following link, and in particular their 100-amp -plus > > (continuous) supplies where the fans do not activate for low draws. You > had > > mentioned something about price not being so important. These ain't > cheap. > > 73 de Mark .w2or. > > > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to wa2...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
I find Mark's point very important. Obtain and use a supply which is more than adequate for the service or load. Thus a 25 amp supply feeding a radio drawing 20+ amps will need lots of cooling. This is not the way to do it. Get a 50 amp supply for a radio drawing 20+ amps and the fan(s) will likely never come on. Go the cheap way and get the cheap results. Do it right and be happy. Don't be a cheap ham and then complain about the product you purchased. There is more to choosing a power supply than volts and amps. How about duty cycle? And CCS rated supplies vs. ICAS rated supplies. Humm... 73 Bob, K4TAX On 6/9/2019 2:12 PM, Mark Murray via Elecraft wrote: Peter, Check out the high amperage 13,8 volt power supplies offered by Samlex America at the following link, and in particular their 100-amp -plus (continuous) supplies where the fans do not activate for low draws. You had mentioned something about price not being so important. These ain't cheap. 73 de Mark .w2or. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
[Elecraft] Silent power supply for a K3s
Peter, Check out the high amperage 13,8 volt power supplies offered by Samlex America at the following link, and in particular their 100-amp -plus (continuous) supplies where the fans do not activate for low draws. You had mentioned something about price not being so important. These ain't cheap. 73 de Mark .w2or. https://www.samlexamerica.com/products/ProductsList.aspx?cid=S3 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
[Elecraft] Silent power supply for a K3s
I use a Pyramid PS-36KX, which is a linear 35 amp supply. It costs about $155 on Amazon. Universal Compact Bench Power Supply - 32 Amp Linear Regulated Home Lab Benchtop AC-to-DC 12V Converter w/ 12-15V DC 115V AC 600 Watt Input, Amperage Gauge Display, Adjustable Voltage - Pyramid PS36KX -- Ron W7HD - NAQCC#7587 OMISS#9898 KX3#6966 LinuxUser#415320 Editor OVARC newsletter __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
I'm using an Astron SS-30M with very satisfactory results. 73 Bob, K4TAX Sent from my iPhone > On Jun 9, 2019, at 9:52 AM, Peter Dougherty wrote: > > Hi all, > I would like to find a power supply to power the K3s that is completely > silent. I've owned an Astron RS-35M, which was great until it started > buzzing like crazy. I swapped that out for a Samlex SEC-1235M, and did the > fan mod to keep the fan on constantly at low speed. The problem here is that > when I'm running FT8 or RTTY for more than about a half hour, the fan goes > into high speed and stays there for an hour or more, long after the rig and > amp's fans have shut off. And because it's a tiny fan moving a lot of air, > it's incredibly loud. > > I'm looking for an RF-clean power supply (either linear or switching) that > can deliver 25A continuously without requiring a cooling fan of any kind. > All it's running is the K3s/P3 and a couple of boxes with less than 1A draw > each. The front panel meter on the Samlex is showing a tad over 20A when > transmitting 100W in FT8/RTTY. Any suggestions? Within reason, cost isn't a > major issue. > > > - > 73 and Good DX > Peter, W2IRT > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to rmcg...@blomand.net > __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
I've installed modern, silent fans in nearly every piece of equipment I own, including my Samlex 1235. They're not expensive and come in all standard sizes. Can't hear my PC or power supply fans at all from a few feet away. Look for Nanoxia Deep Silence fans. (No, I'm not retrofitting my Elecraft gear...) https://www.amazon.com/gp/product/B00CHW8L1Y/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 Gary NA6O __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
I have an RM-50M at present. To cut a lot of the audible hum I have it setting on some plastic rings that fell out of a light fixture (d'oh!) and it is thus supported on the bottom plate the transformer mounts to rather than the feet of the supply. As I have the supply under the desk, I just reached over with my foot and by pressing on the top cover I can cut the audible level considerably more. I may have to investigate a fix for this. 73, Nate, N0NB -- "The optimist proclaims that we live in the best of all possible worlds. The pessimist fears this is true." Web: http://www.n0nb.us GPG key: D55A8819 GitHub: N0NB __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
Whatever you do, don't take the path I did: https://www.worldwidedx.com/threads/megawatt-vs-chinese-imitation-30-amp-switching-power-supply-comparison.182976/page-7#post-578238 73, Nate, N0NB -- "The optimist proclaims that we live in the best of all possible worlds. The pessimist fears this is true." Web: http://www.n0nb.us GPG key: D55A8819 GitHub: N0NB __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
I've been running an Astron RS-35A for several years now, fortunately withoutany buzzing. However, I use it to feed a WMR PG40S, which keeps a large (105Ah)AGM SLA battery charged, and that feeds a RigRunner. I adjusted the RS-35A to14.1 V on the RigRunner (on receive), and it dips to 13.5 or so on transmitwhen running the K3 at 100W out. As others have mentioned, it is a case of using large wire - #10 or #8 - in the shortestlengths possible, and the heavier-rated APPs throughout. There are numerous articles out on the web and in the archives of this mailing list aboutamendments to Astron power supplies and depending on the age of yours, you may needto investigate what the root cause of the buzzing is, be it simply loose fastening hardwareor perhaps a filter capacitor that's well past its prime. HTH, Brandy, N1HO On Sunday, June 9, 2019, 10:54:23 AM EDT, Peter Dougherty wrote: Hi all, I would like to find a power supply to power the K3s that is completely silent. I've owned an Astron RS-35M, which was great until it started buzzing like crazy. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
I found that there is a terminal block inside most Astron Power Supplies, that sometimes gets mounted on a painted surface. I always check all Astron supplies I buy, new or used, to insure the paint has been removed under the ground connection of the internal terminal block. In about 50% of the supplies I have seen over the years, the TB has been mounted on a painted surface. 73s and thanks, Dave (NK7Z) https://www.nk7z.net ARRL Technical Specialist ARRL Volunteer Examiner ARRL Asst. Director, NW Division, Technical Resource On 6/9/19 7:52 AM, Peter Dougherty wrote: Hi all, I would like to find a power supply to power the K3s that is completely silent. I've owned an Astron RS-35M, which was great until it started buzzing like crazy. I swapped that out for a Samlex SEC-1235M, and did the fan mod to keep the fan on constantly at low speed. The problem here is that when I'm running FT8 or RTTY for more than about a half hour, the fan goes into high speed and stays there for an hour or more, long after the rig and amp's fans have shut off. And because it's a tiny fan moving a lot of air, it's incredibly loud. I'm looking for an RF-clean power supply (either linear or switching) that can deliver 25A continuously without requiring a cooling fan of any kind. All it's running is the K3s/P3 and a couple of boxes with less than 1A draw each. The front panel meter on the Samlex is showing a tad over 20A when transmitting 100W in FT8/RTTY. Any suggestions? Within reason, cost isn't a major issue. - 73 and Good DX Peter, W2IRT __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to d...@nk7z.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Silent power supply for a K3s
This is an issue that I have also, but have chosen to ignore. I have the samlex, astron ss30 and a rm30. The Quiet one is the rm 30. You might try to tighten the bolts on the transformer. That helped mine, but no fan. One issue is keeping the power cord short to keep from getting a voltage drop. You also have to use the right gauge of wire and 45 amp power pole connectors. So, the power supply has to sit close to the rig. I have a cord of 24 inches. I have very little voltage drop and the K3 runs better at 13.7 than 11.8v. So, I have learned to ignore the fans on ft8, and I wear headphones for the other modes. Your mileage may vary, but if it has a fan you will get noise. The AL 82 also is noisy but that's life. Lee K0WA On Sun, Jun 9, 2019, 9:53 AM Peter Dougherty wrote: > Hi all, > I would like to find a power supply to power the K3s that is completely > silent. I've owned an Astron RS-35M, which was great until it started > buzzing like crazy. I swapped that out for a Samlex SEC-1235M, and did the > fan mod to keep the fan on constantly at low speed. The problem here is > that > when I'm running FT8 or RTTY for more than about a half hour, the fan goes > into high speed and stays there for an hour or more, long after the rig and > amp's fans have shut off. And because it's a tiny fan moving a lot of air, > it's incredibly loud. > > I'm looking for an RF-clean power supply (either linear or switching) that > can deliver 25A continuously without requiring a cooling fan of any kind. > All it's running is the K3s/P3 and a couple of boxes with less than 1A draw > each. The front panel meter on the Samlex is showing a tad over 20A when > transmitting 100W in FT8/RTTY. Any suggestions? Within reason, cost isn't a > major issue. > > > - > 73 and Good DX > Peter, W2IRT > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to lee.bul...@gmail.com > __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
[Elecraft] Silent power supply for a K3s
Hi all, I would like to find a power supply to power the K3s that is completely silent. I've owned an Astron RS-35M, which was great until it started buzzing like crazy. I swapped that out for a Samlex SEC-1235M, and did the fan mod to keep the fan on constantly at low speed. The problem here is that when I'm running FT8 or RTTY for more than about a half hour, the fan goes into high speed and stays there for an hour or more, long after the rig and amp's fans have shut off. And because it's a tiny fan moving a lot of air, it's incredibly loud. I'm looking for an RF-clean power supply (either linear or switching) that can deliver 25A continuously without requiring a cooling fan of any kind. All it's running is the K3s/P3 and a couple of boxes with less than 1A draw each. The front panel meter on the Samlex is showing a tad over 20A when transmitting 100W in FT8/RTTY. Any suggestions? Within reason, cost isn't a major issue. - 73 and Good DX Peter, W2IRT __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com