Re: [Drakelist] Yet another AC-4 rebuild (now :-) completed
FWIW, I found 3 computer switch strips over the past couple years at garage sales and thrift stores. I didn't pay over $2.50 for any one of them. BTW you would be surprised the radio equipment you can find in these places as well. --- On Tue, 1/10/12, Garey Barrell k4...@mindspring.com wrote: From: Garey Barrell k4...@mindspring.com Subject: Re: [Drakelist] Yet another AC-4 rebuild (now :-) completed To: Mark Pilant n1...@arrl.net Cc: 'drakelist' drakelist@zerobeat.net Date: Tuesday, January 10, 2012, 9:47 PM Mark - Here's a suitable one. Rated at 15A, so should handle a couple of T-4X and a receiver or two without problems. http://www.amazon.com/Eliminator-E107/dp/B000OMXZ3I/ref=pd_cp_e_2 Lots more out there, 'computer power center'. 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 Mark Pilant wrote: Hi Garey. I like the idea of individually switched outlets. But I haven't seen any that weren't network/LAN controlled. A little to pricey for me at home. (Although I have used them plenty at work.) 73 - Mark N1VQW _ ___ 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 mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Drakelist Digest, Drake B Line No Output
Fred, Do you have a scope? If so, start looking stage by stage to see where the issue is...then fix that stage. Since you don't have any Spot...it is before the finals for sure. 73, Lee -Original Message- From: FJMelick fjmel...@aol.com To: drakelist drakelist@zerobeat.net Sent: Wed, Jan 11, 2012 12:29 am Subject: Re: [Drakelist] Drakelist Digest, Drake B Line No Output Well, the problem continues. It worked for a short time but is not working again. Replaced V-1 and V2 with tested used tubes. V1 was N.O.S. I did substitution of all the tubes with used and tested tubes without any change in output. The spot position does not put out a signal either. Even when put into AM and using the spot function, I can hardly hear that tone in the receiver either Both VFO's will work the receiver. I have idle current when in tune position or when PTT on mic. no other output. No output when speaking or whistling into the mic either Any other ideas? Where to look next? Sprayed the wafer switches with Deoxit and another plastic safe contact cleaner even though the wafers are phenolic and not plastic. Band switch is not any stiffer than it was when I bought the twins 5 years ago so I don't think that is the problem. I tried 75 meters and 40 meter both with the same results. No output. Where should I start to look for the problem? Any ideas would be appreciated. Thanks 73 de Fred WD8ADG ___ 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] Drake L7 fan needed
Hi folks: I've got a Drake L7 with a noisy fan, and I was thinking of replacing it. Would anybody happen to have one? Thanks! Clark KB9SJD ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Drake T-4XB - No Output
Fred - Please forward the entire message to keep the thread intact. It helps to be able to go back to see what has been done. If you have a scope, close the PTT and check the 5.645 MHz CO signal at the wiper of the BALANCE pot. -OR- If you have a general coverage receiver, see if you can hear the 5.645 MHz CO signal, -OR- IF none of the above, set BAND to 40M, and in TUNE look for a peak in the 80M band of the RF TUNE control. 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 fjmel...@aol.com wrote: /Well, the problem continues./ // / It worked for a short time but is not working again. Replaced V-1 and V2 with tested used tubes. V1 was N.O.S. / // /I did substitution of all the tubes with used and tested tubes without any change in output./ /The spot position does not put out a signal either. Even when put into AM and using the spot function, I can hardly hear that tone in the receiver either/ // /Both VFO's will work the receiver. / // /I have idle current when in tune position or when PTT on mic. no other output. No output when speaking or whistling into the mic either / // /Any other ideas? / // /Where to look next? / // /Sprayed the wafer switches with Deoxit and another plastic safe contact cleaner even though the wafers are phenolic and not plastic. Band switch is not any stiffer than it was when I bought the twins 5 years ago so I don't think that is the problem. / // /I tried 75 meters and 40 meter both with the same results. No output./ // /Where should I start to look for the problem? Any ideas would be appreciated./ // ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Drakelist Digest Drake T4XB No Output
I have been replying to the people that have been kind enough to answer me but I have been answering them directly to their email address. Not sure how to continue my answers so they appear on the drakelist when that happens. I want to keep the thread alive so it can help others that may be having the same problem but I find it hard to do when they send information to me via their email address When I reply it goes directly to the party that sent me the information. Let me know what to do to share this information with the list and I would be glad to do that. 73 de Fred WD8ADG ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] R-4A, NB issues
Garey, Diode D3 appears to be good..and I checked D1 D2 while I was at it. Diode D3: V10b Cathode side 4.5 volts. And it varies in voltage a lot based on. NB is off. SSB signals being rcvd. pulses up a lot with static crashes. The non-cathode side of D3 is 150 vlots if NB is OFF and 30 volts if it is on...no variance with signals rcvd. OK, this AM I discovered with the scope what I think is going on If you tune in ...say a nice 20 over 9 signal on say 40m LSB. Thr RX sounds very nice indeed (Assuming no other strong signal is nearby) THEN...if you either tune to the other sideband OR just move the PB tuner to USBlots of noisey, clicking sounds appear when he modulates. OK, now with the scope...you can see this on the cathode of V10B. Remember NB is OFF. (When on the problem stillhappens, just the pulses look a little better) Now, I looked on the plate of V9 The NB IF amp...WOW...with things normal on LSB good sounding signal I see...around 5-10 volts P-P od SSB signal shape..then when I tune to USB or just move the dial to the opposite side of the sugnal... I Get 60 -100 Volts P-P od signal and that is I beleive triggering the NB. The PB tuner is a stage after this so it is a little confusing what is hapening. If during this failure mode I pull V9 or V10 All is quiet and the RX works fine. Would really appreciate an idea or two as this is well quite a challange (and it will be fun to fix this) Thanks, 73, Lee Lee Simmonds Summit DCS LLC 260-799-4077 Office 260-403-6936 Cell -Original Message- From: Garey Barrell k4...@mindspring.com To: kc9cdt kc9...@aol.com Cc: drakelist drakelist@zerobeat.net Sent: Tue, Jan 10, 2012 11:01 am Subject: Re: [Drakelist] R-4A, NB issues Lee - Check D3 for leakage. Clean switch contact on S3(f) 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 kc9...@aol.com wrote: Hi gang, DX sure has been fun lately! Been working on a R-4A, 11 tube versionit's really sounding good...fixed several problems and did a complete alignment. In thourough testing I discovered a problem...seems the NB is causing clicking or pulse noise on normal signals. That is with it OFF or ON. I can tune through signals and at certain points , depending on the adjacent signals etc I hear the clicking or popping noise during the modulation of the signals. And if I tune in a single signal, a good loud one , then turn the PB tuning to the opposite SB, I can hear the clicking/popping. IF I PULL the NB AMP V10, The problem goes away! So, either the NB is on all the time (even with the sw. off) OR there is a problem in the NB circuit I'll have to find... Before I did in deeperanyone have any ideas on what the problem is?? Thanks, 73, Lee, KC9CDT ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Drake L7 fan needed
Check with Ron Baker, wb4...@wb4hfn.com I believe that he had them in the past. 73 K1NR On Wed, 11 Jan 2012 08:30:36 -0800 (PST) Jim DiMauro radio6...@yahoo.com wrote: Evan: I would assume, that among other things, you're trying to find a replacement with an equivalent air flow spec (CFM). Am I correct? I've not been successful in finding the spec for the original Torin fans that were in my two L-7s. Is that part of your testing? I would certainly be appreciative of your efforts, as would the Drake community at large. 73, Jim W2BVM From: K9sqg k9...@aol.com To: chvjill...@aol.com; drakelist@zerobeat.net Sent: Wednesday, January 11, 2012 10:31 AM Subject: Re: [Drakelist] Drake L7 fan needed Clark, Be very, very careful on this. Finding the right fan for replacing it is harder than one would think. Replacing it with an original fan is NOT necessarily a good solution. Right now I'm doing some testing on a substitute. 73, Evan, K9SQG -Original Message- From: Clark Jillson chvjill...@aol.com To: drakelist drakelist@zerobeat.net Sent: Wed, Jan 11, 2012 5:01 am Subject: [Drakelist] Drake L7 fan needed Hi folks: I've got a Drake L7 with a noisy fan, and I was thinking of replacing it. Would anybody happen to have one? Thanks! Clark KB9SJD ___ 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 - Web mail provided by NuNet, Inc. The Premier National provider. http://www.nni.com/ ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Drakelist Digest Drake T4XB No Output
Do reply All. 73, Lee -Original Message- From: FJMelick fjmel...@aol.com To: drakelist drakelist@zerobeat.net Sent: Wed, Jan 11, 2012 12:25 pm Subject: Re: [Drakelist] Drakelist Digest Drake T4XB No Output I have been replying to the people that have been kind enough to answer me but I have been answering them directly to their email address. Not sure how to continue my answers so they appear on the drakelist when that happens. I want to keep the thread alive so it can help others that may be having the same problem but I find it hard to do when they send information to me via their email address When I reply it goes directly to the party that sent me the information. Let me know what to do to share this information with the list and I would be glad to do that. 73 de Fred WD8ADG ___ 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] Drakelist Digest Drake T4XB No Output
Or if they reply direct ...just copy drakelist@zerobeat.net Lee Simmonds Summit DCS LLC 260-799-4077 Office 260-403-6936 Cell -Original Message- From: FJMelick fjmel...@aol.com To: drakelist drakelist@zerobeat.net Sent: Wed, Jan 11, 2012 12:25 pm Subject: Re: [Drakelist] Drakelist Digest Drake T4XB No Output I have been replying to the people that have been kind enough to answer me but I have been answering them directly to their email address. Not sure how to continue my answers so they appear on the drakelist when that happens. I want to keep the thread alive so it can help others that may be having the same problem but I find it hard to do when they send information to me via their email address When I reply it goes directly to the party that sent me the information. Let me know what to do to share this information with the list and I would be glad to do that. 73 de Fred WD8ADG ___ 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] Fan for T-4XC
Hi, I never saw a fan as an accessory for the T-4XC. Is there any offical one? If not, what what you recommend? Size, diamater, where to put it??? TNX 73 -- Adrin P. van Bloois Antonlaan 104 email: adr...@pa0rda.nl 3701 VG Zeist voice: +31-(0)-30-6912741 The Netherlands fax:NONE 52 05'15.77N 5 4'44.56E QTH-locater JO 22 OC The whole point of cooking is to get as much flavour out of the ingredients as possible. -- Delia Smith -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Fan for T-4XC
Hi Adrian, My recommendation would be simply to mount whatever you might have right available atop the rig, so that it's blowing the hot air generated in the final PA cage OUTWARD... I did some tests awhile back shared the results with this Reflector on how very beneficial the addition of a fan in this way can reduce the warm-up drift frequency excursion of a T-4X like mine. VERY WORTHWHILE addition for the minimal strain it might take to do so, IMHO... ~73~ de Eddy VE3CUI - VE3XZ * On 2012-01-11, at 3:48 PM, Adrian P. van Bloois wrote: Hi, I never saw a fan as an accessory for the T-4XC. Is there any offical one? If not, what what you recommend? Size, diamater, where to put it??? ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Fan for T-4XC
4 muffin fan located on top of the case right above the finals cage, pulling air UP and OUT. Since you are in Europe, 220VAC fans are the norm and might be too loud. Try to find a 24VDC fan and run it on 12vdc. Quietly moves a lot of air. 73 K1NR On Wed, 11 Jan 2012 21:48:40 +0100 Adrian P. van Bloois adr...@pa0rda.nl wrote: Hi, I never saw a fan as an accessory for the T-4XC. Is there any offical one? If not, what what you recommend? Size, diamater, where to put it??? TNX 73 -- Adrin P. van Bloois Antonlaan 104 email: adr...@pa0rda.nl 3701 VG Zeist voice: +31-(0)-30-6912741 The Netherlands fax:NONE 52 05'15.77N 5 4'44.56E QTH-locaterJO 22 OC The whole point of cooking is to get as much flavour out of the ingredients as possible. -- Delia Smith -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist - Web mail provided by NuNet, Inc. The Premier National provider. http://www.nni.com/ ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Fan for T-4XC
Adrian - You don't need a lot of air. Just a 'gentle breeze' that can be totally silent. Computer fans are cheap and quiet. Run a noisy one at a lower voltage/ Easiest to sit on top of the cabinet over the PA, _BLOWING UP_. Rubber or foam 'feet' just to keep it in place and prevent vibration noises. If you don't have room above the transmitter, the fan works just as well mounted on the rear wall of the PA cage, _BLOWING OUT_. 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 Eugene Balinski wrote: 4 muffin fan located on top of the case right above the finals cage, pulling air UP and OUT. Since you are in Europe, 220VAC fans are the norm and might be too loud. Try to find a 24VDC fan and run it on 12vdc. Quietly moves a lot of air. 73 K1NR On Wed, 11 Jan 2012 21:48:40 +0100 Adrian P. van Blooisadr...@pa0rda.nl wrote: Hi, I never saw a fan as an accessory for the T-4XC. Is there any offical one? If not, what what you recommend? Size, diamater, where to put it??? ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] (no subject)
Hi, Thanks guys for the great response. All very similar. :-) It's just what I did to my Yaesu FTDX-400 in 1972. The thing got so hot that you could fry an egg on it. Then I bought a fan, Papst, real robust German thing. The finals were probably cooler than the rest of the rig. BOth fan and rig are still running smoothly. :-) Blowing the air out seems to be the key factor in this. Thanks again, 73 Adrian -- Adrian P. van Bloois Antonlaan 104 email: adr...@pa0rda.nl 3701 VG Zeist voice: +31-(0)-30-6912741 The Netherlands fax:NONE 52 05'15.77N 5 4'44.56E QTH-locater JO 22 OC The whole point of cooking is to get as much flavour out of the ingredients as possible. -- Delia Smith -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Drakelist Digest, Drake B Line No Output
Time for a scope. I still think you've got a contact problem somewhere. The switch wafers in the B's are a big improvement over the A's, but they can still get crudded up. The fact that you can receive on either the transmitter or receiver suggests a problem in either the FUNCTION switch, gain control, or contacts in the tube sockets. Steve Wedge, W1ES/4 Live free or die: Death is not the worst of evils. John Stark. All my computers have my signature with various pearls of wisdom appended thereto. From: fjmel...@aol.com Sent: Wednesday, January 11, 2012 3:34 PM To: w1es1...@earthlink.net Subject: Re: [Drakelist] Drakelist Digest, Drake B Line No Output In a message dated 1/11/2012 12:49:04 P.M. Eastern Standard Time, w1es1...@earthlink.net writes: There's a signal not getting to the final or even the driver, more than likely. You have to break it down: There's the 5595 crystal oscillator that runs regardless of band, the band oscillator that runs at the frequency determined by the band crystal and the PTO output. If you have the transmitter hooked to a receiver, can you receive signals when you turn the control over to the transmitter? If you can, it eliminates the band oscillator and the PTO circuits as the culprits (as well as the premixer). Given that it's intermittent, I'm betting on a dirty contact somewhere - including tube sockets. Steve -Original Message- From: fjmel...@aol.com Sent: Jan 11, 2012 12:13 PM To: w1es1...@earthlink.net Subject: Re: [Drakelist] Drakelist Digest, Drake B Line No Output In a message dated 1/11/2012 11:34:32 A.M. Eastern Standard Time, w1es1...@earthlink.net writes: Fred, when you run in SPOT, do you have the GAIN turned up at all? How about in CW? Steve, W1ES -Original Message- From: fjmel...@aol.com Sent: Jan 11, 2012 12:27 AM To: drakelist@zerobeat.net Subject: Re: [Drakelist] Drakelist Digest, Drake B Line No Output Well, the problem continues. It worked for a short time but is not working again. Replaced V-1 and V2 with tested used tubes. V1 was N.O.S. I did substitution of all the tubes with used and tested tubes without any change in output. The spot position does not put out a signal either. Even when put into AM and using the spot function, I can hardly hear that tone in the receiver either Both VFO's will work the receiver. I have idle current when in tune position or when PTT on mic. no other output. No output when speaking or whistling into the mic either Any other ideas? Where to look next? Sprayed the wafer switches with Deoxit and another plastic safe contact cleaner even though the wafers are phenolic and not plastic. Band switch is not any stiffer than it was when I bought the twins 5 years ago so I don't think that is the problem. I tried 75 meters and 40 meter both with the same results. No output. Where should I start to look for the problem? Any ideas would be appreciated. Thanks 73 de Fred WD8ADG Steve: In spot I don't hear the birdy sound on SSB setting. On the AM setting the sound is very low compared to how it should sound and with the gain advanced I usually hear the mic. but very little mic sound with gain advanced now. Fred WD8ADG Steve: Both Transmitter and Receiver VFO will receive a signal. Fred WD8ADG___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Fan for T-4XC
There never was an official fan. I can remember using a 120V muffin fan, slowed down with a huge, honkin' wire-wound resistor, the first time I used a fan over the finals 25 years ago. Today, we've got a plethora of 12VDC fans - some with thermistor control like the one I got at a hamfest for $4. You can run these off a wall wart or put a little half-wave rectified supply inside the transmitter or receiver - off the filament supply. The 12V fans typically draw about 250 mA. Fans over the receiver transformer also help a lot at keeping heat down! 73, Enjoy Those Drakes but be cool... Steve Wedge, W1ES/4 Live free or die: Death is not the worst of evils. John Stark. All my computers have my signature with various pearls of wisdom appended thereto. -- From: Adrian P. van Bloois adr...@pa0rda.nl Sent: Wednesday, January 11, 2012 3:48 PM To: drakelist@zerobeat.net Subject: [Drakelist] Fan for T-4XC Hi, I never saw a fan as an accessory for the T-4XC. Is there any offical one? If not, what what you recommend? Size, diamater, where to put it??? TNX 73 -- Adrin P. van Bloois Antonlaan 104 email: adr...@pa0rda.nl 3701 VG Zeist voice: +31-(0)-30-6912741 The Netherlands fax: NONE 52 05'15.77N 5 4'44.56E QTH-locater JO 22 OC The whole point of cooking is to get as much flavour out of the ingredients as possible. -- Delia Smith -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. ___ 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] FS: R-4C and T-4XC
The C-line is sold. Thanks to all for the interest. 73, Terry - W8NJR ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Shure 444D Microphone wiring question
I am trying to wire up my old Shure 444D, and find something strange. According to the manual, there are supposed to be red, white, black, and shield wires in the coiled cable. That is what shows coming out of the cable inside the mic base. Red is mic element, shield is also for the mic element, white is PTT, and black is PTT ground. At the plug end of the coiled cable, there is the shield, the black lead which connects to the PTT ground, a red wire which seems to be the switched PTT, blue and yellow wires. What sort of magic is going on in this cable? Any pointers would be appreciated! Steve WA9JML ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Shure 444D Microphone wiring question
On Wed, 11 Jan 2012 21:14:41 -0600, Steve Berg wrote: What sort of magic is going on in this cable? Any pointers would be appreciated! Someone may have replaced the cord at some point. Take the bottom off and see where the wires go. 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
[Drakelist] Inrush Current
Hello All, Congratulations to Mark, N1VQW on his AC-4 Re-build (with the 'Soft Start') and the subsequent comments by Garey, K4OAH and Dick, KE4NS. Etc. I rather like the idea of a remote 'Switch Board'. As far as originality of equipment is concerned could the relay have been mounted outboard in the Speaker Cabinet? But then, how many of us have got fans mounted on the back of equipment PA Cages? The first thing that came to my notice was the reduction of 'Inrush Current', at the switch; 365ma down to 10ma. This must mean longer life for the on/off switch. Although 'Inrush Current' did not seem to be considered a problem many years ago (1950s and '60s) Orr mentions it in his Radio Handbook, 18th. Edition and 22nd Edition. His concern was the possibility of damage to the rectifier diodes (18th. Ed. p781) and vacuum tubes (although this may have only applied to thoriated-tungsten filaments) and rectifier stack (22nd. Ed. p 23.6 and 23.24). Did Collins consider this a problem and if so what did Art do about it? I wonder what else 'Inrush Current' could affect ? I would appreciate any comments anyone would like to make on this topic. After all we are dealing with quite old equipment and the more theoretical and practical knowledge we have, the better (in my opinion). Keep the Drakes on air. Bob ZL2AAQ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Inrush Current
On Thu, 12 Jan 2012 16:55:19 +1300, jeffers...@xtra.co.nz wrote: I wonder what else 'Inrush Current' could affect ? I would appreciate any comments anyone would like to make on this topic. After all we are dealing with quite old equipment and the more theoretical and practical knowledge we have, the better (in my opinion). Historical discussions on this topic: http://www.mail-archive.com/search?l=drakelist%40zerobeat.netq=inrush http://zerobeat.net/drakelist/smf/index.php/topic,252.0.html 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
