Re: [Drakelist] T-4X: put on your thinking caps!
Yes on the caps - absolutely! That particular chassis can is really easy to sub modern caps under the chassis because the points they're wired to are really easy to access. Now here's a funny thing: on 40, I can peak the plate current with the RF TUNE down below 1. This one is looking to be one of those rare ones where I will actually have to measure the slug heights to get to a starting point. Someone must have gone in sometime in the past trying to peak it. The last trimmer to the back (which I believe peaks the driver) on 80 seems to need more capacitance, so looks like I'll have to be replacing some fixed caps in there. Still scratching my head over why only 10m gives me a sidetone in either CW or TUNE. I also hear the faint drone of the sidetone all the time if the gain is advanced - just like in nearly every T-4X I've ever used (you have to listen for it). Ah, well. There will be more time for this one later... 73, Steve, W1ES/4 -Original Message- From: Garey Barrell k4...@mindspring.com Sent: Nov 29, 2011 10:10 PM To: Steve Wedge w1es1...@earthlink.net Cc: Drake List drakelist@zerobeat.net Subject: Re: [Drakelist] T-4X: put on your thinking caps! Steve - Sure sounds like bandswitch. Don't forget to check bandswitch hardware for wafer alignment, AND check wafer center holes for oblong and not round holes!! You DID disconnect the electrolytic caps from the old twist-lok when you tacked in the tubulars? Verify the RF TUNE pointer is aligned properly. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 2-C/2-NT, 4-A, 4-B, C-Line and TR-4/C Service Supplement CDs www.k4oah.com Steve Wedge wrote: I have not taken out the scope or meter yet. Observations are somewhat random. My friend Keith's T-4X spent who knows how many years in a New Hampshire cellar. Keith got it at a hamfest long ago, from parts unknown. It was obvious to me that it had belonged to a smoker and was pretty grungy anyway, so it got the poolside view in my kitchen, followed by the sauna. I could sort of get output on 20m with it prior to its cleansing. It was obvious by the fact that it wouldn't work at all on CW that the can capacitor had dried out. I replaced both caps with modern units under the chassis. I had to sub an 80 uF for the 60 that was there because that's what I had on hand. I haven't tried it on all bands yet, but there's some weird stuff going on here: No output on 40 15 60W is about all it can muster on 80 20 despite tweaking the trimmers. The rear 80m trimmer needs to go in more but is against its stop A couple of watts out on 10. No sidetone - except on 10m. No real output on 10 (it's like 3 W). There's a somewhat chirpy sidetone on 10 only. Neutralization must be way off, as max out on 20 doesn't match the dip. I'm thinking the switch wafers need some Cramolin applied with a toothpick (yes, I still have a bottle of the stuff!). The good news is that all the low-level stuff seems to be working as far as frequency control. All the tubes tested good on a TV-10 D/U except the finals which I can't check on that tester. Why would I only get any sort of sidetone on 10m? Take your time, as I'll be setting this aside so that I can get to the two R-4B's I have waiting that I know I can clean, de-mod and align fairly quickly compared to this sad rig. I was hoping it was only going to be an alignment and a set of finals away from finishing, but I'll have to save this for later. The R-4B's await - Keith told me no rush Smile emoticon 73, I do suspect Steve Wedge, W1ES/4 I swear by my life, and my love of it, that I will never live for the sake of another man, nor ask another man to live for mine. -Ayn Rand. All my computers have my signature with various pearls of wisdom appended thereto. ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] T-4X: put on your thinking caps!
See below... 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 2-C/2-NT, 4-A, 4-B, C-Line and TR-4/C Service Supplement CDs www.k4oah.com Steve Wedge wrote: Yes on the caps - absolutely! That particular chassis can is really easy to sub modern caps under the chassis because the points they're wired to are really easy to access. Now here's a funny thing: on 40, I can peak the plate current with the RF TUNE down below 1. This one is looking to be one of those rare ones where I will actually have to measure the slug heights to get to a starting point. Someone must have gone in sometime in the past trying to peak it. Sounds like either you have a coil failure or the slugs have been misadjusted. Watch for a broken slug as well. | The last trimmer to the back (which I believe peaks the driver) on 80 seems to need more capacitance, so looks like I'll have to be replacing some fixed caps in there. Yes, that sounds like perhaps another Dur-Mica failure! :-) | Still scratching my head over why only 10m gives me a sidetone in either CW or TUNE. Probably a switching problem. | I also hear the faint drone of the sidetone all the time if the gain is advanced - just like in nearly every T-4X I've ever used (you have to listen for it). SIDETONE 'backwave' is usually high esr in C132, allowing the tone to couple 'around' the keyswitch, D8, via the Plate supply for V9a and V9b. D8 itself is also the problem sometimes, usually indicated by a junction voltage increase (greater than -0.7 VDC) in receive. Ah, well. We do this for fun ... There will be more time for this one later... 73, Steve, W1ES/4 -Original Message- From: Garey Barrellk4...@mindspring.com Sent: Nov 29, 2011 10:10 PM To: Steve Wedgew1es1...@earthlink.net Cc: Drake Listdrakelist@zerobeat.net Subject: Re: [Drakelist] T-4X: put on your thinking caps! Steve - Sure sounds like bandswitch. Don't forget to check bandswitch hardware for wafer alignment, AND check wafer center holes for oblong and not round holes!! You DID disconnect the electrolytic caps from the old twist-lok when you tacked in the tubulars? Verify the RF TUNE pointer is aligned properly. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 2-C/2-NT, 4-A, 4-B, C-Line and TR-4/C Service Supplement CDs www.k4oah.com Steve Wedge wrote: I have not taken out the scope or meter yet. Observations are somewhat random. My friend Keith's T-4X spent who knows how many years in a New Hampshire cellar. Keith got it at a hamfest long ago, from parts unknown. It was obvious to me that it had belonged to a smoker and was pretty grungy anyway, so it got the poolside view in my kitchen, followed by the sauna. I could sort of get output on 20m with it prior to its cleansing. It was obvious by the fact that it wouldn't work at all on CW that the can capacitor had dried out. I replaced both caps with modern units under the chassis. I had to sub an 80 uF for the 60 that was there because that's what I had on hand. I haven't tried it on all bands yet, but there's some weird stuff going on here: No output on 40 15 60W is about all it can muster on 80 20 despite tweaking the trimmers. The rear 80m trimmer needs to go in more but is against its stop A couple of watts out on 10. No sidetone - except on 10m. No real output on 10 (it's like 3 W). There's a somewhat chirpy sidetone on 10 only. Neutralization must be way off, as max out on 20 doesn't match the dip. I'm thinking the switch wafers need some Cramolin applied with a toothpick (yes, I still have a bottle of the stuff!). The good news is that all the low-level stuff seems to be working as far as frequency control. All the tubes tested good on a TV-10 D/U except the finals which I can't check on that tester. Why would I only get any sort of sidetone on 10m? Take your time, as I'll be setting this aside so that I can get to the two R-4B's I have waiting that I know I can clean, de-mod and align fairly quickly compared to this sad rig. I was hoping it was only going to be an alignment and a set of finals away from finishing, but I'll have to save this for later. The R-4B's await - Keith told me no rush Smile emoticon 73, I do suspect Steve Wedge, W1ES/4 I swear by my life, and my love of it, that I will never live for the sake of another man, nor ask another man to live for mine. -Ayn Rand. All my computers have my signature with various pearls of wisdom appended thereto. ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[Drakelist] Heathkit Shop AC4 Kit
Have been using the AC4 with the Heathkit shop now for a couple of weeks and it is great to be back to getting good audio reports. Still have the AC3 and the TR4 project to work on this winter. Drakes are great in the shack when it starts to get cold outside. ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[Drakelist] Stability Test and FAN
The results with this third (and final---I promise!) test were most interesting (NOTE: for comparative purposes, I have square-bracketed---[ ]---the changes observed at the very same time intervals in the FIRST test, at the end of each observation line). Here goes: (1) 5455.0-KHz (cold start)---[0.0-Khz]; (2) 5455.0-KHz (unchanged)---[0.0-KHz]; (3) 5454.3-KHz (downward drift of 700-Hz from cold start)---[500-Hz]; (4) 5453.7 KHz (downward drift of 1.3-KHz from cold start)---[1.0-KHz]; (5) 5453.2-KHz (downward drift of 1.8-KHz from cold start)---[1.2-KHz], and, (6) 5453.2-KHz (unchanged)---[0.0-KHz0 The end result in terms of PTO drift with the fan off was 1.8-KHz, versus 1.2-KHz with the fan on. Interesting! That's a difference of 600-Hz, or HALF of the drift experienced with the fan running! Thanks for doing this test! It is about what I get on the R4B as well. The fan test is interesting I have thought about putting a fan on but never have. If I do it would be nice to have a nice quiet fan. Is there an advantage to a DC fan? It seems a AC fan might be easier to wire up? ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Stability Test and FAN
On 2011-11-30, at 3:13 PM, Paul Gerhardt wrote: The fan test is interesting I have thought about putting a fan on but never have. If I do it would be nice to have a nice quiet fan. Is there an advantage to a DC fan? It seems a AC fan might be easier to wire up? Hi Paul, I used whatever it was that I happened to have on hand at the time, specifically, a small 12 VDC cooling fan that I think was extricated from a junked desk top computer... I power it with a wall wart DC power supply, and it's really unobtrusive in terms of noise. Mine is simply bolted on the top half of the T-4X enclosure, directly above the cage housing the final PA tubes. Mine blows the hot air OUT of the T-4X, rather than blowing outside cooling air into it. For the amount of work $$$ expended in incorporating it---and keeping in mind the benefits by doing so---I think that the addition of a cooling fan is a ...must have, rather than a ...nice to have feature... ~73~ de Eddy VE3CUI - VE3XZ ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Stability Test and FAN
I put one of the silenx fans on my R4B. Cannot hear it running. THese are SUPER quiet fans. I can take a picture but used a small rectifier and cap off the filament supply..just like the T4X. The fan mounts with double sided foam tapeover the slot between the rear plate and the power transformer. I used a small business card stock baffle to direct the air flow out between the transf. Pix later tonite. You will not regret these fans. Curt KU8L On 11/30/2011 3:13 PM, Paul Gerhardt wrote: The results with this third (and final---I promise!) test were most interesting (NOTE: for comparative purposes, I have square-bracketed---[ ]---the changes observed at the very same time intervals in the FIRST test, at the end of each observation line). Here goes: (1) 5455.0-KHz (cold start)---[0.0-Khz]; (2) 5455.0-KHz (unchanged)---[0.0-KHz]; (3) 5454.3-KHz (downward drift of 700-Hz from cold start)---[500-Hz]; (4) 5453.7 KHz (downward drift of 1.3-KHz from cold start)---[1.0-KHz]; (5) 5453.2-KHz (downward drift of 1.8-KHz from cold start)---[1.2-KHz], and, (6) 5453.2-KHz (unchanged)---[0.0-KHz0 The end result in terms of PTO drift with the fan off was 1.8-KHz, versus 1.2-KHz with the fan on. Interesting! That's a difference of 600-Hz, or HALF of the drift experienced with the fan running! Thanks for doing this test! It is about what I get on the R4B as well. The fan test is interesting I have thought about putting a fan on but never have. If I do it would be nice to have a nice quiet fan. Is there an advantage to a DC fan? It seems a AC fan might be easier to wire up? ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] T-4X: put on your thinking caps!
I was starting to think maybe I put the crystals back in in reverse order, but I couldn't have been that lucky :) Ah, well, the T-4X is over in the corner for now and will require all my tools to troubleshoot. I started on the first of the two R-4B's tonight, have dismantled and washed it and it's now in the oven drying. 73, Steve Wedge, W1ES/4 I swear by my life, and my love of it, that I will never live for the sake of another man, nor ask another man to live for mine. -Ayn Rand. All my computers have my signature with various pearls of wisdom appended thereto. -- From: Garey Barrell k4...@mindspring.com Sent: Wednesday, November 30, 2011 9:35 AM To: Steve Wedge w1es1...@earthlink.net Cc: Drake List drakelist@zerobeat.net Subject: Re: [Drakelist] T-4X: put on your thinking caps! See below... 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 2-C/2-NT, 4-A, 4-B, C-Line and TR-4/C Service Supplement CDs www.k4oah.com Steve Wedge wrote: Yes on the caps - absolutely! That particular chassis can is really easy to sub modern caps under the chassis because the points they're wired to are really easy to access. Now here's a funny thing: on 40, I can peak the plate current with the RF TUNE down below 1. This one is looking to be one of those rare ones where I will actually have to measure the slug heights to get to a starting point. Someone must have gone in sometime in the past trying to peak it. Sounds like either you have a coil failure or the slugs have been misadjusted. Watch for a broken slug as well. | The last trimmer to the back (which I believe peaks the driver) on 80 seems to need more capacitance, so looks like I'll have to be replacing some fixed caps in there. Yes, that sounds like perhaps another Dur-Mica failure! :-) | Still scratching my head over why only 10m gives me a sidetone in either CW or TUNE. Probably a switching problem. | I also hear the faint drone of the sidetone all the time if the gain is advanced - just like in nearly every T-4X I've ever used (you have to listen for it). SIDETONE 'backwave' is usually high esr in C132, allowing the tone to couple 'around' the keyswitch, D8, via the Plate supply for V9a and V9b. D8 itself is also the problem sometimes, usually indicated by a junction voltage increase (greater than -0.7 VDC) in receive. Ah, well. We do this for fun ... There will be more time for this one later... 73, Steve, W1ES/4 -Original Message- From: Garey Barrellk4...@mindspring.com Sent: Nov 29, 2011 10:10 PM To: Steve Wedgew1es1...@earthlink.net Cc: Drake Listdrakelist@zerobeat.net Subject: Re: [Drakelist] T-4X: put on your thinking caps! Steve - Sure sounds like bandswitch. Don't forget to check bandswitch hardware for wafer alignment, AND check wafer center holes for oblong and not round holes!! You DID disconnect the electrolytic caps from the old twist-lok when you tacked in the tubulars? Verify the RF TUNE pointer is aligned properly. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 2-C/2-NT, 4-A, 4-B, C-Line and TR-4/C Service Supplement CDs www.k4oah.com Steve Wedge wrote: I have not taken out the scope or meter yet. Observations are somewhat random. My friend Keith's T-4X spent who knows how many years in a New Hampshire cellar. Keith got it at a hamfest long ago, from parts unknown. It was obvious to me that it had belonged to a smoker and was pretty grungy anyway, so it got the poolside view in my kitchen, followed by the sauna. I could sort of get output on 20m with it prior to its cleansing. It was obvious by the fact that it wouldn't work at all on CW that the can capacitor had dried out. I replaced both caps with modern units under the chassis. I had to sub an 80 uF for the 60 that was there because that's what I had on hand. I haven't tried it on all bands yet, but there's some weird stuff going on here: No output on 40 15 60W is about all it can muster on 80 20 despite tweaking the trimmers. The rear 80m trimmer needs to go in more but is against its stop A couple of watts out on 10. No sidetone - except on 10m. No real output on 10 (it's like 3 W). There's a somewhat chirpy sidetone on 10 only. Neutralization must be way off, as max out on 20 doesn't match the dip. I'm thinking the switch wafers need some Cramolin applied with a toothpick (yes, I still have a bottle of the stuff!). The good news is that all the low-level stuff seems to be working as far as frequency control. All the tubes tested good on a TV-10 D/U except the finals which I can't check on that tester. Why would I only get any sort of sidetone on 10m? Take your time, as I'll be setting this aside so that I can get to the two R-4B's I have waiting that I know I can clean, de-mod and align fairly quickly compared to this sad rig. I was hoping it was only going to be an alignment and a set of finals away from finishing, but I'll
Re: [Drakelist] Stability Test and FAN
I run a PC fan over my T-4XB, also using a wall-wart. I found this fan at a hamfest for $5 and it has a thermistor sensor in the airflow that will allow the fan to run at max speed if it gets sufficiently warm. This is a nice extra! I just stuck some rubber feet on my fan and it rests on top. I periodically have to move it back over after a few days, but it avoids having to drill/enlarge any holes. Steve Wedge, W1ES/4 I swear by my life, and my love of it, that I will never live for the sake of another man, nor ask another man to live for mine. -Ayn Rand. All my computers have my signature with various pearls of wisdom appended thereto. From: Eddy Swynar Sent: Wednesday, November 30, 2011 3:27 PM To: Paul Gerhardt Cc: drakelist@zerobeat.net Subject: Re: [Drakelist] Stability Test and FAN On 2011-11-30, at 3:13 PM, Paul Gerhardt wrote: The fan test is interesting I have thought about putting a fan on but never have. If I do it would be nice to have a nice quiet fan. Is there an advantage to a DC fan? It seems a AC fan might be easier to wire up? Hi Paul, I used whatever it was that I happened to have on hand at the time, specifically, a small 12 VDC cooling fan that I think was extricated from a junked desk top computer... I power it with a wall wart DC power supply, and it's really unobtrusive in terms of noise. Mine is simply bolted on the top half of the T-4X enclosure, directly above the cage housing the final PA tubes. Mine blows the hot air OUT of the T-4X, rather than blowing outside cooling air into it. For the amount of work $$$ expended in incorporating it---and keeping in mind the benefits by doing so---I think that the addition of a cooling fan is a ...must have, rather than a ...nice to have feature... ~73~ de Eddy VE3CUI - VE3XZ ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[Drakelist] Stability Test and FAN
Hi, Paul: I purchased a T4-XC with MS-4 speaker and AC-4 on the cheap. The rig, etc., are in really nice shape and the cabinets of the T4-XC and MS-4 had been repainted beautifully. The T4-XC had an 80-mm square dc fan on the back of the PA cage. Two screws to mount it at the top and a tie wrap on the left hand side (as viewed from the back). On inspection, the feed for the fan was the 12.6Vac filament line with only a 1N4000-series diode in series. The fan runs very quietly; it is produced by PPM, (Pony Precision Motor Co. in Taiwan), model FBA-9, brushless and ball bearing. Any 12Vdc fan would probably work and you can find the 80-mm fans in abundance from the computer stores. If you want a higher speed from the fan, add an electrolytic capacitor the output of the rectifier to increase the average dc voltage. 73, Bob K9JU ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Stability Test and FAN
Here are the links to the photo albums for the Fan install on the T4XB and R4B. It has made a HUGE difference in the operating temperature of the transformer and area around it. And these fans are really quiet. For the R4B: https://picasaweb.google.com/captcurt08/R4BFan?authkey=Gv1sRgCP_B8eCBk669Wg For T4X and AC4: https://picasaweb.google.com/captcurt08/DrakeFanInstall Hope this helps Curt KU8L On 11/30/2011 4:33 PM, Chris Kepus wrote: Curt, I would be most appreciative if you sent your picture(s) to me as well. Just call me a fan(also). ;-) 73, Chris W7JPG -Original Message- From: drakelist-boun...@zerobeat.net [mailto:drakelist-boun...@zerobeat.net] On Behalf Of Curt Sent: Wednesday, November 30, 2011 12:50 PM To: drakelist@zerobeat.net Subject: Re: [Drakelist] Stability Test and FAN I put one of the silenx fans on my R4B. Cannot hear it running. THese are SUPER quiet fans. I can take a picture but used a small rectifier and cap off the filament supply..just like the T4X. The fan mounts with double sided foam tapeover the slot between the rear plate and the power transformer. I used a small business card stock baffle to direct the air flow out between the transf. Pix later tonite. You will not regret these fans. Curt KU8L ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] T-4X: put on your thinking caps!
Oven temp that won't harm plastic? I am going to need the same thing for several projects. I had simply planned to use Warm for 24 hours, but would love to hear your (or anyone else's) version Steve!!! Thanks. Ed Tanton website: http://www.n4xy.com All emails IN OUT checked by Norton AntiVirus with AutoProtect -- Wag more / Bark less -- ///snip Ah, well, the T-4X is over in the corner for now and will require all my tools to troubleshoot. I started on the first of the two R-4B's tonight, have dismantled and washed it and it's now in the oven drying. 73, Steve Wedge, W1ES/4 ///snip ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Stability Test and FAN
On Wed, 30 Nov 2011 19:46:36 -0500, Steve Wedge wrote: This is a nice extra! I just stuck some rubber feet on my fan and it rests on top. I periodically have to move it back over after a few days, but it avoids having to drill/enlarge any holes. Hve you tried those thin adhesive magnetic strips? They should keep the fan from walking, and you would elimiate the air gap. 73 -Jim -- Ham Radio NU0C Lincoln, Nebraska, U.S.S.A. TR7/RV7/R7A/L7, TR6/RV6, T4XC/R4C/L4B, NCL2000, SB104A, R390A, GT550A/RV550A, HyGain 3750, IBM PS/2 - all vintage, all the time! Give a man a URL, and he will learn for an hour; teach him to Google, and he will learn for a lifetime. HyGain 3750 User's Group - http://groups.yahoo.com/group/HyGain_3750/ http://incolor.inetnebr.com/jshorney http://www.nebraskaghosts.org ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Baked Drakes
Never leave the PTO, meter or any other plastics like that on the rig when baking. I always remove the PTO, meter, front panel and, of course all knobs and tubes. It's basically a stripped chassis when it gets its wash and dry. Never submerge - only wash with brushes and detergent, rinse thoroughly with the sink sprayer above and below, then pour distilled water over it. I take the rigs out to the shed before the oven for an encounter with an air gun. That will remove most of the water. Yes, you have to re-oil everything when you're done and on the A and B receivers I also recommend removing the PBT coil carriage after cleaning to clean the dried-out grease from the assembly. The equipment looks and smells much better and runs cooler. After 40 - 50 years, even a clean-looking chassis is hiding a lot of dirt. Steve Wedge, W1ES/4 I can't complain, but sometimes I still do. - Joe Walsh If the above message appears, it came from Steve's Son of Laptop! - Original Message - From: Ed Tanton n...@comcast.net To: 'Steve Wedge' w1es1...@earthlink.net; Drakelist@zerobeat.net Sent: Wednesday, November 30, 2011 9:46 PM Subject: RE: [Drakelist] T-4X: put on your thinking caps! Oven temp that won't harm plastic? I am going to need the same thing for several projects. I had simply planned to use Warm for 24 hours, but would love to hear your (or anyone else's) version Steve!!! Thanks. Ed Tanton website: http://www.n4xy.com All emails IN OUT checked by Norton AntiVirus with AutoProtect -- Wag more / Bark less -- ///snip Ah, well, the T-4X is over in the corner for now and will require all my tools to troubleshoot. I started on the first of the two R-4B's tonight, have dismantled and washed it and it's now in the oven drying. 73, Steve Wedge, W1ES/4 ///snip ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Stability Test and FAN
You can get the same airflow by running a larger fan at a lower speed with the benefit being lower audible noise. I have some surplus 4 fans that have rubber feet attached and just sit over the hot portion of the cabinet. I run them at a DC value below their ratings. They don't walk, aren't heard, and substantially lower the peak temps within the radio. Dennis AE6C On Wed, Nov 30, 2011 at 5:21 PM, Bob Loving bob.lov...@sbcglobal.netwrote: Hi, Paul: I purchased a T4-XC with MS-4 speaker and AC-4 on the cheap. The rig, etc., are in really nice shape and the cabinets of the T4-XC and MS-4 had been repainted beautifully. The T4-XC had an 80-mm square dc fan on the back of the PA cage. Two screws to mount it at the top and a tie wrap on the left hand side (as viewed from the back). On inspection, the feed for the fan was the 12.6Vac filament line with only a 1N4000-series diode in series. The fan runs very quietly; it is produced by PPM, (Pony Precision Motor Co. in Taiwan), model FBA-9, brushless and ball bearing. Any 12Vdc fan would probably work and you can find the 80-mm fans in abundance from the computer stores. If you want a higher speed from the fan, add an electrolytic capacitor the output of the rectifier to increase the average dc voltage. 73, Bob K9JU ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Stability Test and FAN
Great point! I have two large fans on my L-7PS, 12 volt fans connected in series on a 12 volt power supply. They are barely audible if I really listen for them with no other noise in the room. The IBM ethernet switch on the shelf behind me easily drowns them out. And they do still move a good volume of air. 73 -Jim On Wed, 30 Nov 2011 20:07:23 -0800, Dennis Monticelli wrote: You can get the same airflow by running a larger fan at a lower speed with the benefit being lower audible noise. I have some surplus 4 fans that have rubber feet attached and just sit over the hot portion of the cabinet. I run them at a DC value below their ratings. They don't walk, aren't heard, and substantially lower the peak temps within the radio. -- Ham Radio NU0C Lincoln, Nebraska, U.S.S.A. TR7/RV7/R7A/L7, TR6/RV6, T4XC/R4C/L4B, NCL2000, SB104A, R390A, GT550A/RV550A, HyGain 3750, IBM PS/2 - all vintage, all the time! Give a man a URL, and he will learn for an hour; teach him to Google, and he will learn for a lifetime. HyGain 3750 User's Group - http://groups.yahoo.com/group/HyGain_3750/ http://incolor.inetnebr.com/jshorney http://www.nebraskaghosts.org ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Baked Drakes
- Original Message - From: Robert Fish rwf...@comcast.net To: Steve Wedge w1es1...@earthlink.net Cc: drakelist@zerobeat.net Sent: Wednesday, November 30, 2011 7:23 PM Subject: Re: [Drakelist] Baked Drakes Hey Steve, How long and at what temp? I would worry about getting water in the IF cans etc. Does it just bake out? ? Thanks, Bob K6GGO I will repeat the method used at Hewlett-Packard many years ago. First step was to remove anything that could be damaged by water or heat. All closed compartments were opened. Then the chassis was rinsed with warm water from a hose. Then sprayed with a paint spray gun filled with a solution of water and dishwashing detergent and also brushed if necessary with a bottle brush. After washing it was again rinsed off with the hose and warm water. Then blown out with compressed air to remove as much water as possible. Then it was baked in a thermostatically controlled electric oven at about 130F for at least 48 hours. I preferred to keep stuff in there for a week if it was available. Then whatever was removed was replaced and the instrument checked on a metered variac. This procedure took off pretty much anything other than serious fungus (that stuff went to the factory and I don't know what they did with it). -- Richard Knoppow Los Angeles WB6KBL dickb...@ix.netcom.com ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[Drakelist] What makes up the front end
Exactly what components constitute the front end of the R4A? ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
