[Drakelist] 17JB6 NOS tubes
I was sorting through tubes and I have found 5 NOS 17JB6 and 7 NOS 17JB6A. Is there any use for these tubes with Drake equipment? Mike W6MXV ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Dayton and Drake forum--is there one?
Hi Evan and everybody on the list, My wife and I will be coming over to this year's Dayton Hamvention. The planetickets were booked today. We are looking forward to meet many of you at The Drake Forum! We will be arriving to Atlanta, GA, on Wedneday May 13, and our departure will be on Sunday May 24, also from Atlanta. So it will be great to have one and a half week vacation in USA again. We love to drive around, and we'll be heading north for Dayton first. See you in Dayton! 73, Sindre, LA6OP - Original Message - From: k9...@aol.com To: wa7...@charter.net ; drakelist@zerobeat.net Sent: Saturday, March 14, 2009 1:58 AM Subject: Re: [Drakelist] Dayton and Drake forum--is there one? Drake Forum is Saturday of Hamvention weekend. 130-245 PM. Room 4. Agenda is being finalized but you won't want to miss it. We're going to have some rain on one of the days of the big event, beyond that, I can't say, hi hi. Welcome to Dayton and the Dayton Hamvention. ** Need a job? Find employment help in your area. (http://yellowpages.aol.com/search?query=employment_agenciesncid=emlcntusyelp0005) -- ___ 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] Article in April 2009 QST
Hello, Did anyone read the article on modernizing a TR-7 by DK4DDS. It has information on adding a ton of features, such as DSP Noise reduction, curing the PTO Drift, Notch Filter, Improving the sensevity on the higher bands, Speech Processor and a bunch of others. It is some great food for thought, for bringing a great radio into the 21st Century. Great Stuff. I'm thinking very hard about trying most of them out. Most of them do not require modifing the original Circuit boards, just adding boards. If anybody had some comments/information on these mods, I sure would be interested. Best, DW Holtman WB7SSN ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Article in April 2009 QST
Personal opinion follows... In a word, YUK! It's like jacking up a Jeep and putting a Corvette engine, transmission and wheels under it. What you end up with is neither a Jeep nor a Corvette, but a collection of parts. Much better to sell the TR-7, take the money you'd spend on the improvements, and buy a new YaeComWood. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B, C-Line TR-4/C Service Supplement CDs www.k4oah.com DW Holtman wrote: Hello, Did anyone read the article on modernizing a TR-7 by DK4DDS. It has information on adding a ton of features, such as DSP Noise reduction, curing the PTO Drift, Notch Filter, Improving the sensevity on the higher bands, Speech Processor and a bunch of others. It is some great food for thought, for bringing a great radio into the 21st Century. Great Stuff. I'm thinking very hard about trying most of them out. Most of them do not require modifing the original Circuit boards, just adding boards. If anybody had some comments/information on these mods, I sure would be interested. Best, DW Holtman WB7SSN ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Article in April 2009 QST
Agreed Garey! I have a better suggestion though: keep the TR7 and if it is so needed, buy that ugly ricebox in addition. Soon finding out that it is nice to go back to the TR7 from time to time :) Best 73, Dick PA2DW Op Mon, 16 Mar 2009 22:19:20 +0100 schreef Garey Barrell k4...@mindspring.com: Personal opinion follows... In a word, YUK! It's like jacking up a Jeep and putting a Corvette engine, transmission and wheels under it. What you end up with is neither a Jeep nor a Corvette, but a collection of parts. Much better to sell the TR-7, take the money you'd spend on the improvements, and buy a new YaeComWood. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B, C-Line TR-4/C Service Supplement CDs www.k4oah.com DW Holtman wrote: Hello, Did anyone read the article on modernizing a TR-7 by DK4DDS. It has information on adding a ton of features, such as DSP Noise reduction, curing the PTO Drift, Notch Filter, Improving the sensevity on the higher bands, Speech Processor and a bunch of others. It is some great food for thought, for bringing a great radio into the 21st Century. Great Stuff. I'm thinking very hard about trying most of them out. Most of them do not require modifing the original Circuit boards, just adding boards. If anybody had some comments/information on these mods, I sure would be interested. Best, DW Holtman WB7SSN ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist -- Gemaakt met Opera's revolutionaire e-mailprogramma: http://www.opera.com/mail/ ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Article in April 2009 QST
You said it, Garey. What a terrible idea. It's a waste of a radio, time, manpower, and money. Lee, w0vt - Original Message - From: Garey Barrell k4...@mindspring.com To: Drakelist drakelist@zerobeat.net Sent: Monday, March 16, 2009 4:19:20 PM GMT -06:00 US/Canada Central Subject: Re: [Drakelist] Article in April 2009 QST Personal opinion follows... In a word, YUK! It's like jacking up a Jeep and putting a Corvette engine, transmission and wheels under it. What you end up with is neither a Jeep nor a Corvette, but a collection of parts. Much better to sell the TR-7, take the money you'd spend on the improvements, and buy a new YaeComWood. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B, C-Line TR-4/C Service Supplement CDs www.k4oah.com DW Holtman wrote: Hello, Did anyone read the article on modernizing a TR-7 by DK4DDS. It has information on adding a ton of features, such as DSP Noise reduction, curing the PTO Drift, Notch Filter, Improving the sensevity on the higher bands, Speech Processor and a bunch of others. It is some great food for thought, for bringing a great radio into the 21st Century. Great Stuff. I'm thinking very hard about trying most of them out. Most of them do not require modifing the original Circuit boards, just adding boards. If anybody had some comments/information on these mods, I sure would be interested. Best, DW Holtman WB7SSN ___ 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] Cancel Membership
Please conacel membership. I no longer have interest in Drake equipment. Jim Wise w4pro___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Article in April 2009 QST
I think you need an additional opinion on this! First, the QST article is a very poor condensed version of the DK4DDS (PA1HFO) mods that have been floating around for a few years now. For some inexplicable reason, many of his solutions were left completely out of the article (e.g. solution for power output not flat, and solution for low sensitivity on the higher bands. ) I don't think it's worth all the work to install all of the mods shown in the article, but the ones NOT shown are interesting. The sensitivity of the TR7 is certainly lacking on the higher bands and a good preamp is a great addition and doesn't require any metal work. I bought one of the DF4NW preamps and you can turn it on/off by using one of the TR7 front panel pushbuttons that's very rarely used for its original purpose. The other DK4DDS mod I found interesting (not in the QST article) was the PIN diode attenuator board that allows you to set the drive control to the same position and get the same output on all bands. If you operate CW with your TR7, you might also want to look into the key click mod (see the WB4HFN site for that). I just checked the magazine, and see that they left out the PTO stabilizer mod as well. That one can be added without extending the cabinet in any way and is documented on the Web. Personally, I prefered to address that problem with an outboard DDS VFO which has served me quite well for a while now. 73, Floyd - K8AC - Original Message - From: DW Holtman tubest...@comcast.net To: Drakelist drakelist@zerobeat.net Sent: Monday, March 16, 2009 4:51 PM Subject: [Drakelist] Article in April 2009 QST Hello, Did anyone read the article on modernizing a TR-7 by DK4DDS. It has information on adding a ton of features, such as DSP Noise reduction, curing the PTO Drift, Notch Filter, Improving the sensevity on the higher bands, Speech Processor and a bunch of others. It is some great food for thought, for bringing a great radio into the 21st Century. Great Stuff. I'm thinking very hard about trying most of them out. Most of them do not require modifing the original Circuit boards, just adding boards. If anybody had some comments/information on these mods, I sure would be interested. Best, DW Holtman WB7SSN ___ 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] Voltage Reulator in R-4a Question
Good Afternoon All: Here is something I have been seeing now for a while. In my R-4a, every cold start in the morning, the OB2 flickers and glows VERY bright. From an angle, it looks like there are flames on the inside of the rcvr. I almost spilled my coffe all over trying to get back to the switch the first time I saw this. It will go on for quite some time and eventually die down to the normal red glow. If I cycle the power a couplle of times, it will usually stop and show a normal glow on the second or third restart. I originally thought it was because of relatively low morning temps in the shack..about 55 degrees, but it seems there is really no corelation to temperature--occasionally after running for 6-10 hours, it will just start the really bright flickering. I have replaced the OB2 and checked all components and voltages around this area and they are all proper. The radio has been re-capped and all PS voltages are nominal. There is no detectable noise or other performance change while this is ocurring that I can tell but in 40 years of ownership, this has only been happening lately. Any Ideas?? Thanks Curt KU8L ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Article in April 2009 QST
It's like jacking up a Jeep and putting a Corvette engine, transmission and wheels under it. What you end up with is neither a Jeep nor a Corvette, but a collection of parts. But it might just create a tool that performs an intended purpose better than either original...and perhaps better than any other Off the Shelf tool. I think is an interesting approach...not every piece of Drake equipment has to be maintained in original configuration. Many of these additions were things that Drake would have added had they continued in the business. If approaches like this were never taken, the highly sought after Sherwood Drakes would not be so popular. Finally, using an old Drake in upgraded form beats having it sit on some shelf only being used as a B or C rig because it isn't quite up to the technical challenge of some of todays operating. Just my .02, Curt KU8L ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] 17JB6 NOS tubes
I may remember someone in Europe using them in Drakes. It would either take a separate power supply (not hard to do) or some voltage multiplier/resistor combination (not that hard either). Some day we may be grateful to get (any)JB6's. With a lot of 12, I would not throw them away. I would sell them as a lot or keep them until we need them. 73, Bob WW3QB --- On Mon, 3/16/09, MICHAEL TALLENT mwtall...@comcast.net wrote: From: MICHAEL TALLENT mwtall...@comcast.net Subject: [Drakelist] 17JB6 NOS tubes To: Drakelist drakelist@zerobeat.net, Drake-qth dr...@mailman.qth.net Date: Monday, March 16, 2009, 2:31 AM I was sorting through tubes and I have found 5 NOS 17JB6 and 7 NOS 17JB6A. Is there any use for these tubes with Drake equipment? Mike W6MXV ___ 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] TR-4 Plate Meter bounce
The meters in my TR-3 are very bouncy. They are also magnetically coupled together, so one will drag the other a bit and cause more bouncing. I was told the early meters did this. This may be different than your problem. 73, Bob WW3QB --- On Sat, 3/14/09, STEVE SCOGGINS ke...@yahoo.com wrote: From: STEVE SCOGGINS ke...@yahoo.com Subject: [Drakelist] TR-4 Plate Meter bounce To: drakelist@zerobeat.net Date: Saturday, March 14, 2009, 1:56 AM I am working on rebuilding/cleanup of a TR-4 transceiver. The rig is working ok, except for a bouncing (irratic) plate meter problem. The meter oscillates when you place the rig in tune. The meter continues to bounce after switching from TX back to RX. The 2 ohm meter shunt is ok. Thanks for your help, Steve N9HE -Inline Attachment Follows- ___ 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] Voltage Reulator in R-4a Question
Well, it's obvious that the original configuration is obsolete and needs to be replaced by a piece of silicon!! :-) Actually the flashing in VR tubes is often seen with leakage of air past the pin seals. I have had several NOS tubes that have exhibited this behavior. You may need to try more than one or two to find a good one. Cold ambient temps cause momentary flashes at startup, as does high voltage from those pesky solid-state rectifiers that apply HV before the tubes warm up enough to pull the B+ down from the peak value. But generally it's air..Guess these would be airy tubes, as opposed to gassy tubes. :-) 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B, C-Line TR-4/C Service Supplement CDs www.k4oah.com Curt Nixon wrote: Good Afternoon All: Here is something I have been seeing now for a while. In my R-4a, every cold start in the morning, the OB2 flickers and glows VERY bright. From an angle, it looks like there are flames on the inside of the rcvr. I almost spilled my coffe all over trying to get back to the switch the first time I saw this. It will go on for quite some time and eventually die down to the normal red glow. If I cycle the power a couplle of times, it will usually stop and show a normal glow on the second or third restart. I originally thought it was because of relatively low morning temps in the shack..about 55 degrees, but it seems there is really no corelation to temperature--occasionally after running for 6-10 hours, it will just start the really bright flickering. I have replaced the OB2 and checked all components and voltages around this area and they are all proper. The radio has been re-capped and all PS voltages are nominal. There is no detectable noise or other performance change while this is ocurring that I can tell but in 40 years of ownership, this has only been happening lately. Any Ideas?? Thanks Curt KU8L ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Article in April 2009 QST
On Mon, 16 Mar 2009 17:19:20 -0400, Garey Barrell wrote: It's like jacking up a Jeep and putting a Corvette engine, transmission and wheels under it. What you end up with is neither a Jeep nor a Corvette, but a collection of parts. I'll add my never to be humble opinions to this, already expressed privately to Garey. I skimmed the article briefly, but have read the original incarnation on the WWW. Apparently the article is publically available at: http://www.arrl.org/files/qst-binaries/QS0409vanStralen.zip (12 MB download) Adds an Audio Notch filter, DSP, Speech Processor, DAFC _AND_ LEDs in place of the bulbs! Ugh. Digital junk. Takes away from the charm of the rig, and tends to generate crud and get in the way of the signal. DSP isn't all it's cracked up to be. I've got a RadShack DSP that I used now and again, mostly to reduce high frequency hiss in headphones when doing linear Oscar downlinks on 10 meters. Haven't used it in years, don't really miss it. I found that with a GOOD quality reciever ahead of it, the DSP didn't really add that much. The notch filter might be worthwhile, but I have an R7A now. And the aforementioned RadShack DSP has an auto-notch that workd fairly well. Higher-end esternal DSP boxen are even better in this regard, but nothing beats a true IF notch. The speech processor looks to be audio, can't be as effective as an SP7 (or similar design) RF speech processor. Old tech wins on this one. My LEDs are better. :) DAFC isn't such a big deal, the rig is pretty stable *if you have the fan installed correctly* (and it's not thermostaticlally controlled)! A bunch of little boards stuck under the parent board, That block the test points for frequency alignments Further stuff on the ARRL Binaries site, another 13 MB (zipped), adding a PA drive Attenuator with 16 transistors!, a Preamplifier, DDS PTO replacement, AND of course a new fan, temperature controlled, blowing IN I'm staying away from the digital and DDS stuff. More failure points, possible introduction of digital noise, etc. Although I did occasionally use a preamp on 10 meters for satellite, it's not really necessary. I'm getting respectable MDS numbers out of the TR7, and it seems to be pretty flat across the HF band. It is definitely more than enough to hear the local noise floor on 10 meters under quiet conditions. The only benefit of a preamp is to amplify weak signals under quiet conditions to make them easier to hear; the downside is your IP3 goes down when you turn the preamp on. Not good during sunspots or running in a 'test. The TR7 IS NOT DEAF on 10 meters! Let's end this myth. I thought this fan nonsense was laid to rest, I PROVED that the fan works better when installed as intended. I invited others to duplicate my experiments to confirm or refute my findings, and no one has yet done so. You have to examine the fan as part of a COOLING SYSTEM, rather than as a device to spot cool one area. And it doesn't even do that as well when blowing in. I will continue to be vocal about that (as well as that awful Drake allband transmit mod)! Not to be totally negative, this gentleman has gone to an awful lot of work and appears to have done some quality work. I applaud his skills and initiative. If I had the tools and resources that he obviously does, I would probably convert my GT550A to a 4CX250 PA deck. I just think that a lot of this is not appropriate or unnecessary, and some could be done just as easily (and perhaps better) with external accessories. 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://radiojim.exofire.net http://incolor.inetnebr.com/jshorney http://www.nebraskaghosts.org ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Article in April 2009 QST
On Mon, 16 Mar 2009 19:04:02 -0400, Curt Nixon wrote: Finally, using an old Drake in upgraded form beats having it sit on some shelf only being used as a B or C rig because it isn't quite up to the technical challenge of some of todays operating. I haven't met a challenge yet that I couldn't meet with my TR7 or C-line. My TR7 has been invited back to our club's Field Day this year for, I think, the fourth year in a row to run 20 fone. These are guys that have access to modern rigs. 73 -Jim (yes, I get to go with 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://radiojim.exofire.net http://incolor.inetnebr.com/jshorney http://www.nebraskaghosts.org ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Article in April 2009 QST
Floyd - The rest of the mods are shown in the Extended version of the article on the ARRL Binary site. Certainly there are mods that can improve the TR-7 over what was do-able almost 35 years ago. I just _personally_ prefer to use these and other period rigs as designed. Things like the key click mod, and others that cure signal quality quirks should be done, no sense inflicting my Luddite-ness on someone else who didn't sign on for it! :-) I have no quarrel with external modifications or accessories such as your DDS VFO, although I find the TR-7 with the fan _blowing out_ more than stable enough for my operations. And when, if ever, the Sun gets spotty again a preamp might be worthwhile! Again, no argument with those who do, it's not like there are only a few all-original TR-7s around for the future archaeologists! 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B, C-Line TR-4/C Service Supplement CDs www.k4oah.com K8AC wrote: I think you need an additional opinion on this! First, the QST article is a very poor condensed version of the DK4DDS (PA1HFO) mods that have been floating around for a few years now. For some inexplicable reason, many of his solutions were left completely out of the article (e.g. solution for power output not flat, and solution for low sensitivity on the higher bands. ) I don't think it's worth all the work to install all of the mods shown in the article, but the ones NOT shown are interesting. The sensitivity of the TR7 is certainly lacking on the higher bands and a good preamp is a great addition and doesn't require any metal work. I bought one of the DF4NW preamps and you can turn it on/off by using one of the TR7 front panel pushbuttons that's very rarely used for its original purpose. The other DK4DDS mod I found interesting (not in the QST article) was the PIN diode attenuator board that allows you to set the drive control to the same position and get the same output on all bands. If you operate CW with your TR7, you might also want to look into the key click mod (see the WB4HFN site for that). I just checked the magazine, and see that they left out the PTO stabilizer mod as well. That one can be added without extending the cabinet in any way and is documented on the Web. Personally, I prefered to address that problem with an outboard DDS VFO which has served me quite well for a while now. 73, Floyd - K8AC - Original Message - From: DW Holtman tubest...@comcast.net To: Drakelist drakelist@zerobeat.net Sent: Monday, March 16, 2009 4:51 PM Subject: [Drakelist] Article in April 2009 QST Hello, Did anyone read the article on modernizing a TR-7 by DK4DDS. It has information on adding a ton of features, such as DSP Noise reduction, curing the PTO Drift, Notch Filter, Improving the sensevity on the higher bands, Speech Processor and a bunch of others. It is some great food for thought, for bringing a great radio into the 21st Century. Great Stuff. I'm thinking very hard about trying most of them out. Most of them do not require modifing the original Circuit boards, just adding boards. If anybody had some comments/information on these mods, I sure would be interested. Best, DW Holtman WB7SSN ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Article in April 2009 QST
On Mon, 16 Mar 2009 18:50:18 -0400, K8AC wrote: The sensitivity of the TR7 is certainly lacking on the higher bands and a good preamp is a great addition and doesn't require any metal work. I bought one of the DF4NW preamps and you can turn it on/off by using one of the TR7 front panel pushbuttons that's very rarely used for its original purpose. My sensitivity measurements don't bear this out. Sensitivity is relatively flat across the HF spectrum, and I did all of my critical measurements on 10 meters. 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://radiojim.exofire.net http://incolor.inetnebr.com/jshorney http://www.nebraskaghosts.org ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Voltage Reulator in R-4a Question
I had the same behavior in my early serial R4-B. It's quite a light show in a darkened room. The cause is definitely a bad VR tube in which there has been air ingress. Just stick another tube in there. Dennis AE6C On Mon, Mar 16, 2009 at 7:24 PM, Garey Barrell k4...@mindspring.com wrote: Well, it's obvious that the original configuration is obsolete and needs to be replaced by a piece of silicon!! :-) Actually the flashing in VR tubes is often seen with leakage of air past the pin seals. I have had several NOS tubes that have exhibited this behavior. You may need to try more than one or two to find a good one. Cold ambient temps cause momentary flashes at startup, as does high voltage from those pesky solid-state rectifiers that apply HV before the tubes warm up enough to pull the B+ down from the peak value. But generally it's air..Guess these would be airy tubes, as opposed to gassy tubes. :-) 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B, C-Line TR-4/C Service Supplement CDs www.k4oah.com Curt Nixon wrote: Good Afternoon All: Here is something I have been seeing now for a while. In my R-4a, every cold start in the morning, the OB2 flickers and glows VERY bright. From an angle, it looks like there are flames on the inside of the rcvr. I almost spilled my coffe all over trying to get back to the switch the first time I saw this. It will go on for quite some time and eventually die down to the normal red glow. If I cycle the power a couplle of times, it will usually stop and show a normal glow on the second or third restart. I originally thought it was because of relatively low morning temps in the shack..about 55 degrees, but it seems there is really no corelation to temperature--occasionally after running for 6-10 hours, it will just start the really bright flickering. I have replaced the OB2 and checked all components and voltages around this area and they are all proper. The radio has been re-capped and all PS voltages are nominal. There is no detectable noise or other performance change while this is ocurring that I can tell but in 40 years of ownership, this has only been happening lately. Any Ideas?? Thanks Curt KU8L ___ 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] Article in April 2009 QST
On Mon, 16 Mar 2009 23:12:06 -0400, Garey Barrell wrote: I have no quarrel with external modifications or accessories such as your DDS VFO, I will admit the DDS VFO idea looks interesting, and I understand they have made great strides in the DDS area in the past few years. To me, there's something about a digital VFO that doesn't *feel* like a radio! But that's personal preference. I don't think I'll do the DDS thing for Drake. Although I do have some wild ideas about multiple RV7s on the TR7/R7 combination I think the switching capability is there to do some interesting stuff. Can you say four independant analog VFOs? Who needs memories. :) However, considering the relative rarity and expense of the external VFO for my HyGain 3750, I may look at the DDS idea down the road for that application. 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://radiojim.exofire.net http://incolor.inetnebr.com/jshorney http://www.nebraskaghosts.org ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
