Re: [drakelist] TR7 2nd IF Audio board: redux and question on R1136
Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- That would be R1058 and R1060 on the PBT/Reference board. These resistors are a part of an attenuator for the BFO injection signal to the MC1496 mixer. R1058 is changed from 220 ohms to 68 ohms, and R1060 is removed, was 68 ohms. 73, Garey - K4OAH Glen Allen, VA Drake 2-B, 4-B, C-Line TR-4/C Service Supplement CDs www.k4oah.com [EMAIL PROTECTED] wrote: Hey Steve: Although I will probably never find it in my storage room, I do have a copy of a letter regarding the version 2 IF board...I believe it was from Bill Frost, but can't guarantee it.. The point is/was that 2 resistors are changed on another circuit board when using the version 2 IF board.and, no I don't remember which circuit board. If anybody has this information, it may solve part of your gain problem. 73's GL Bill W6FF Santa Barbara, Ca. = - Original Message - *From:* [EMAIL PROTECTED] mailto:[EMAIL PROTECTED] *To:* drakelist@zerobeat.net mailto:drakelist@zerobeat.net *Sent:* Monday, June 09, 2008 10:28 PM *Subject:* Re: [drakelist] TR7 2nd IF Audio board: redux and question on R1136 I have S/N 6951 and it has a version 1 IF board. I have tried 2 different version 2 boards ( which I know are in good working order) and they work but I cannot get the s-meter to adjust: with the version one board my radio reads S9 at 28 MHz but both version 2 boards read S8 or a little lower when reading the calibrator signal. Do I have to adjust R1136 receiver sensitivity to get all boards to react the same? Steve KD2ED -- Submissions:drakelist@zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net --
Re: [drakelist] TR7 2nd IF Audio board: redux and question on R1136
Many thanks to Garey and Bill: Let me see if I can track those resistors down and I'll post the results. I wondered if it might be something like that as all in all either version board seems to work. 73's Steve KD2ED **Vote for your city's best dining and nightlife. City's Best 2008. (http://citysbest.aol.com?ncid=aolacg0005000102)
Re: [drakelist] TR7 2nd IF Audio board: redux and question on R1136
I have noticed that typically the S meter on the version one boards are Scotch compared to the version 2 boards. There are several changes to the S meter circuit, and if memory serves me right, the AGC circuit also, on the version 2. I have tried to update the earlier board with the new changes with mixed results. Since its strictly and issue with the S meter, and not receiver performance, I have learned to live with it. 73, Gary
Re: [drakelist] TR7 2nd IF Audio board: redux and question on R1136
I have S/N 6951 and it has a version 1 IF board. I have tried 2 different version 2 boards ( which I know are in good working order) and they work but I cannot get the s-meter to adjust: with the version one board my radio reads S9 at 28 MHz but both version 2 boards read S8 or a little lower when reading the calibrator signal. Do I have to adjust R1136 receiver sensitivity to get all boards to react the same? Steve KD2ED In a message dated 5/25/2008 11:59:08 A.M. Eastern Daylight Time, [EMAIL PROTECTED] writes: Hi, Does anyone know about when, by serial number, Drake went to the newer version 2nd IF-Audio board? As much time has passed, I know that unless one is sure his/her radio is original, it may be hard to tell due to possible board changes before the current owner. But does someone out there has a good idea? FYI, my current TR7 is SN, 5392, split rear panel, late version NB, Late version pre-driver, early version digital control board and early version IF/Audio. I may be wrong, but the NB is likely a newer addition. I did notice that my IF/audio board has been repaired, an IC replaced and a poor soldering job that I had to clean up. I guess, bottom line, I'm trying to figure out if my audio board is original to the radio or not. Thanks, David WD9CMD **Vote for your city's best dining and nightlife. City's Best 2008. (http://citysbest.aol.com?ncid=aolacg0005000102)
