Re: [Drakelist] new R4B member of the family
There should not be the sensitivity difference you are experiencing. My guess is that the 4A could use an alignment. If you haven't actually tested the tubes or done a few swaps, you might try that too. BTW, congrats on the 4B. That is the only Drake I have and I am similarly very pleased with it. Dennis AE6C On Fri, Apr 17, 2009 at 6:13 PM, Chuck Grandgent ch...@chuckg.com wrote: Well the purpose of this post is twofold: First, despite periodic negative reports about the eB** place, I wanted to report my just received acquisition of a very nice R4B. Decent price, decent shipping charge, very well packed, nicely bound copy of the R4B manual plus misc other relevant R4x articles, received approx three days from the end of the bidding (USPS Priority). I don't recognize the call from being on this list, so I won't identify unless there's a reason to. In short, I couldn't be more pleased. The second reason for the post is about my R4A, and the diff between it and he R4B. I have to say, I have been happy with the R4A over the appro 10 years I have owned it. I have had to do a fair amount of work on it in the AGC section, but I have done lots of great QSO's with it. And to be fair, it lives in my garage, here in No. Florida, and what with the heat, humidity, and insects, it has not had an easy life. Anyway, my first impressioin on powering up the R4B is, that it is SO MUCH MORE SENSITIVE than my R4A, including the S-meter response. Nevermind that the switches seem a lot cleaner, the tuning knob spins easier, etc.. So anyway, I wanted to ask, where would you first begin to look in the R4A to account for the difference in sensitivity between it and the R4B I just got ? I have checked all tube pin voltages, and they do agree closely with what they should be, and I believe the tubes are OK. Chuck, K1OM, Alachua, FL ___ 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] TR3 knobs
wa7...@charter.net writes: selling them under the Philmore brand in blister packs and it was Philmore # 3050. They are listed as 1 diameter . Highlight the Philmore # 3050 and search it, you have them for $ .79 each. Carl wd8nhk **Access 350+ FREE radio stations anytime from anywhere on the web. Get the Radio Toolbar! (http://toolbar.aol.com/aolradio/download.html?ncid=emlcntusdown0003) ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] new R4B member of the family
Chuck - Depending upon the s/n of your R-4A, the two receivers are almost identical, electrically. So there is a reason for the apparent difference! 1. Check the voltage, with a HIGH-Z meter, (not a cheapy DMM,) at TP-2. On top of the chassis, under the Passband Tuner shaft. Should be -1.35 VDC, and this sets the sensitivity of the receiver. If you have done AGC work, you probably know this, but ... 2. Check that the S-Meter ZERO is correct, and that the meter reads 60 dB over S9, (full scale,) with the RF GAIN at full CCW. 3. Most likely weak tubes are V4 and V5, since this is where most of the receiver gain is. Finally, one of the problems with the Drake receivers is their excellent AGC system. The basic system is so good, that ALL signals seem to be at about the same level in the speaker, and you have only the S-Meter to tell you which are the strong ones and which are the weak ones. Really the only way to compare the receivers is with a calibrated signal generator. I really like the little XG-1/2 by Elecraft or the S9 by NORCAL. Both give you a known 1 uV signal ( ~S1-2) and a known 50 uV signal (S-9) at various frequencies. You just have to tie a long piece of yarn or something to them to keep from losing them on the bench! You can do a touch-up alignment in about ten minutes, using the Calibrator and the S-Meter. Typically the transformers do NOT need adjustment, and a simple peaking of the trimmers for the RF, MIXER and PREMIXER stages are all that is needed. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B, C-Line TR-4/C Service Supplement CDs www.k4oah.com Chuck Grandgent wrote: Well the purpose of this post is twofold: First, despite periodic negative reports about the eB** place, I wanted to report my just received acquisition of a very nice R4B. Decent price, decent shipping charge, very well packed, nicely bound copy of the R4B manual plus misc other relevant R4x articles, received approx three days from the end of the bidding (USPS Priority). I don't recognize the call from being on this list, so I won't identify unless there's a reason to. In short, I couldn't be more pleased. The second reason for the post is about my R4A, and the diff between it and he R4B. I have to say, I have been happy with the R4A over the appro 10 years I have owned it. I have had to do a fair amount of work on it in the AGC section, but I have done lots of great QSO's with it. And to be fair, it lives in my garage, here in No. Florida, and what with the heat, humidity, and insects, it has not had an easy life. Anyway, my first impressioin on powering up the R4B is, that it is SO MUCH MORE SENSITIVE than my R4A, including the S-meter response. Nevermind that the switches seem a lot cleaner, the tuning knob spins easier, etc.. So anyway, I wanted to ask, where would you first begin to look in the R4A to account for the difference in sensitivity between it and the R4B I just got ? I have checked all tube pin voltages, and they do agree closely with what they should be, and I believe the tubes are OK. Chuck, K1OM, Alachua, FL ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] TR3 knobs
Carl - Not exactly.. The Drake knob is 0.915 dia, and 0.750 high. Certainly close, and probably ok if you replace them all, but Alan's knobs are correct, made by the same company that made them originally. Pays your money.. :-) 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B, C-Line TR-4/C Service Supplement CDs www.k4oah.com gypsym...@aol.com wrote: wa7...@charter.net writes: selling them under the Philmore brand in blister packs and it was Philmore # 3050. They are listed as 1 diameter . Highlight the Philmore # 3050 and search it, you have them for $ .79 each. Carl wd8nhk ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[Drakelist] Fw: FS: Complete Drake TR4CWrit Station
- Original Message - From: jch39_99 To: drakera...@yahoogroups.com Sent: Saturday, April 18, 2009 9:21 AM Subject: [DrakeRadio] FS: Complete Drake TR4CWrit Station FS: Complete Drake TR4CWrit Station I made a mistake. Last year I got a Drake TR7 and really liked that rig. So this year I thought I would try Drake's best tube transceiver, the TR4CWrit. Got great signal reports on 40 mtr SSB and CW, but it just is not my cup of tea, prefer the TR7. It is too nice of a rig to just sit and gather dust, so I am selling the TR4CWrit (sn#45368) a 9 out of 10 with manual. Also included is the MS4 speaker, the AC4 power supply, a Shure CB41 desk mike, K4OH's Service information for the TR4C series CD, and a nearly full set of replacement tubes (most NOS, the rest good used ones). Hook up an antenna and you are on the air with a great classic tube station. Not DOA but sold as is. $999 plus $100 shipping to lower 48 states. Postal money order or PayPal + 3%. Save the shipping by picking up within 50 miles of Hendersonville, NC. Pictures available. Tnx for looking. jcharley at bellsouth dot net. 73/Crit/K4BXN __._,_.___ . __,_._,__ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] new R4B member of the family
Excellent suggestions, all. I'm going to print them all out and go through it methodically. I do have a URM-25D in good calibration. So I'll make some notes as I go along, and note its performance before I muck with it. I do feel a bit foolish, when I got home and unpacked it and powered it up, I guess band conditions were very good, a bit quieter on the bands this morning :) Thanks to all, Chuck, K1OM On Sat, Apr 18, 2009 at 10:11 AM, Garey Barrell k4...@mindspring.comwrote: Chuck - Depending upon the s/n of your R-4A, the two receivers are almost identical, electrically. So there is a reason for the apparent difference! 1. Check the voltage, with a HIGH-Z meter, (not a cheapy DMM,) at TP-2. On top of the chassis, under the Passband Tuner shaft. Should be -1.35 VDC, and this sets the sensitivity of the receiver. If you have done AGC work, you probably know this, but ... 2. Check that the S-Meter ZERO is correct, and that the meter reads 60 dB over S9, (full scale,) with the RF GAIN at full CCW. 3. Most likely weak tubes are V4 and V5, since this is where most of the receiver gain is. Finally, one of the problems with the Drake receivers is their excellent AGC system. The basic system is so good, that ALL signals seem to be at about the same level in the speaker, and you have only the S-Meter to tell you which are the strong ones and which are the weak ones. Really the only way to compare the receivers is with a calibrated signal generator. I really like the little XG-1/2 by Elecraft or the S9 by NORCAL. Both give you a known 1 uV signal ( ~S1-2) and a known 50 uV signal (S-9) at various frequencies. You just have to tie a long piece of yarn or something to them to keep from losing them on the bench! You can do a touch-up alignment in about ten minutes, using the Calibrator and the S-Meter. Typically the transformers do NOT need adjustment, and a simple peaking of the trimmers for the RF, MIXER and PREMIXER stages are all that is needed. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B, C-Line TR-4/C Service Supplement CDs www.k4oah.com Chuck Grandgent wrote: Well the purpose of this post is twofold: First, despite periodic negative reports about the eB** place, I wanted to report my just received acquisition of a very nice R4B. Decent price, decent shipping charge, very well packed, nicely bound copy of the R4B manual plus misc other relevant R4x articles, received approx three days from the end of the bidding (USPS Priority). I don't recognize the call from being on this list, so I won't identify unless there's a reason to. In short, I couldn't be more pleased. The second reason for the post is about my R4A, and the diff between it and he R4B. I have to say, I have been happy with the R4A over the appro 10 years I have owned it. I have had to do a fair amount of work on it in the AGC section, but I have done lots of great QSO's with it. And to be fair, it lives in my garage, here in No. Florida, and what with the heat, humidity, and insects, it has not had an easy life. Anyway, my first impressioin on powering up the R4B is, that it is SO MUCH MORE SENSITIVE than my R4A, including the S-meter response. Nevermind that the switches seem a lot cleaner, the tuning knob spins easier, etc.. So anyway, I wanted to ask, where would you first begin to look in the R4A to account for the difference in sensitivity between it and the R4B I just got ? I have checked all tube pin voltages, and they do agree closely with what they should be, and I believe the tubes are OK. Chuck, K1OM, Alachua, FL ___ 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] I Fried my T-4XC
Bob - Another one bites the dust! :-) Select R58 so that the meter indicates 70 mA when the current is 70 mA. Calculate actual current against actual MEASURED value of R59. Then select nearest value resistor for correct indication. Don't worry about meter accuracy anywhere else, not important. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B, C-Line TR-4/C Service Supplement CDs www.k4oah.com Robert Ladden wrote: Epilogue: R59 looked good visually, but fell apart when tapped. Cannot trust appearances. Box from Mouser arrived today. It took me about 90 minutes to replace five resistors (I'm slow). Replaced the finals. Powered up, everything looked good. Finals neutralized easily. Full power available. All is well again. By measuring the voltage drop across my new 5% R59, it seems my meter reads 20 mills low. Who knows how accurate it was before. I have not played with R58 yet. While the T-4XC was sick, I used my TR-3 and a near junk RV-3 to work S04R. My thanks again to Garey for the R59 idea and his service CD. And thanks to all for the other things to check and your support. 73, Bob WW3QB --- On Sun, 4/12/09, Garey Barrell k4...@mindspring.com wrote: From: Garey Barrell k4...@mindspring.com Subject: Re: [Drakelist] I Fried my T-4XC To: drakelist@zerobeat.net Date: Sunday, April 12, 2009, 12:52 PM Bob - You've gotten a lot of good suggestions. The Bias supply is always the first suspect in this sort of problem, but you say it is ok. One thing I haven't seen is to check the meter shunt resistor, R59. This is a 3.3 ohm, 1/2W resistor that is located on the relay board under the chassis. This resistor is almost certainly damaged, usually going up in value, causing the meter to read way high. When you replace it, you need to calibrate it using the resistor R58 which is located up on the slide switch behind the LOAD control. You will need to replace the cathode resistors, the screen resistors and certainly need to check the RF chokes. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B, C-Line TR-4/C Service Supplement CDs www.k4oah.com Robert Ladden wrote: I had an unfortunate accident. I was using my T-4XC in CW. I finished but left it in CW mode. I was doing something else in the basement (where the shack is) when I heard a fizzle. I saw the T-4XC turn off. I ran to it and saw the 6JB6's fade from orange. The keyer did something bad, and I was not paying attention (never leave it in CW mode). Not good, but I have several spare 6JB6's. The fuse in the AC-4 blew. I replace the fuse and the 6JB6's and it powers up again. I try to neutralize the finals on 10m but get little output and high current. Not good. I try on 40m and it does tune, but at .4 on the meter I get low output. Trying the load control gets full output, but pegs the current meter and I cannot dip the plate. I quickly turn it off. Cathode resistors test inline at 16 and 30 Ohms. Needs replacing, but probably not the source of this problem. Tuning is too weird. There is no obvious burns on the chokes or anywhere else, but I fear for the bandswitch back there. Hard to get a good look. Is there more I can check? Or is it time for an expert surgeon? 73, Bob WW3QB ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
