Re: [drakelist] Tr-4 problem again
Al Parker [EMAIL PROTECTED] made an utterance to the drakelist gang -- Hi Karl, It sounds to me like you have moved the oscillator frequency in the wrong direction and gotten it outside one of the filter's freq. It should be between the 2 filters. Didn't you add some capacitance to the freq. trimmer a while ago? Maybe you needed less cap, but zero cap probably wouldn't have moved it enough in the proper direction, so could be the xtal's gone south a bit. I've been there once or twice. 73, Al, W8UT New Bern, NC BoatAnchors appreciated here http://www.thecompendium.net/radio/ http://www.hammarlund.info - Original Message - From: Karl Corder [EMAIL PROTECTED] To: drakelist drakelist@www.zerobeat.net Sent: Monday, December 19, 2005 11:15 PM Subject: [drakelist] Tr-4 problem again I have tried adjusting the balanced modulator and the carrier (c130)and neither one will allow the sideband switch in the X position to give me any drive at all beyond the .1 miliamps. With the sideband switch in the NON X position I can get drive and adjust the resting drive current to the .15 as they recommend. I cannot get equal noise pitch using the C130. As long as the sideband switch is in the NON X position and the other switch is in the X-CW position I can get drive but as soon as I put the ssb switch in the X position there isn't any drive from the rf gain control. Does this mean that one or both of the ssb filters have croaked? I can hear (make out signals in the lower sideband but they are poor and hard to tune in the audio isn't good at all, it is bassy and the usb mode is Hissy( can't change it to bassy or bassy to hissy). Appreciate any recommendations? Karl Corder wa20vj -- Submissions:drakelist@www.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] Tr-4 problem again
Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Karl - The bassy and hissy audio on the sidebands indicates the Carrier Oscillator is off frequency. Normally, the two filters form a letter M, with the Carrier Oscillator in the middle. As the carrier moves to one side of 9.000 MHz, the audio response goes bassy on USB and hissy on LSB. If the carrier moves the other way, then the bassy and hissy are reversed. Do you have an accurate frequency counter? Or a modern digital readout transceiver? The Carrier Oscillator should be on 9.000 MHz in the non -X mode and approximately 9.001 MHz in the -X mode. If it is NOT, and cannot be set to frequency by adjusting C130, then you likely have a bad crystal. If it is, or if it can be set to 9.000 MHz by adjusting C130, then tune in a stable CW signal on any band. This signal could be another transmitter loaded into a dummy load, etc. Tune slowly through this signal while watching the S meter. The meter should show no signal, then rise rapidly, then stay relatively constant for about 2.5 kHz, then drop rapidly as you tune through the signal. Do this in both sideband positions. If the S meter reading does not follow this pattern as you tune through a signal, (may stay up less than 2.5 kHz, or may have a dip in the center,) then you likely have a bad filter. Filters from parted out units show up on EBay from time to time, BUT may also be bad. The INRAD filters are excellent, but they are $100 each, which doesn't make much sense in a $250 transceiver unless it has sentimental value! 73, Garey - K4OAH Atlanta Drake C-Line Service Manual http://www.k4oah.com Karl Corder wrote: I have tried adjusting the balanced modulator and the carrier (c130)and neither one will allow the sideband switch in the X position to give me any drive at all beyond the .1 miliamps. With the sideband switch in the NON X position I can get drive and adjust the resting drive current to the .15 as they recommend. I cannot get equal noise pitch using the C130. As long as the sideband switch is in the NON X position and the other switch is in the X-CW position I can get drive but as soon as I put the ssb switch in the X position there isn't any drive from the rf gain control. Does this mean that one or both of the ssb filters have croaked? I can hear (make out signals in the lower sideband but they are poor and hard to tune in the audio isn't good at all, it is bassy and the usb mode is Hissy( can't change it to bassy or bassy to hissy). Appreciate any recommendations? Karl Corder wa20vj -- Submissions:drakelist@www.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] Tr-4 problem again
F3WT [EMAIL PROTECTED] made an utterance to the drakelist gang -- Hi Garey, Very clear explanation below! I have a related question I was wondering about for a while: Why were TR4s - and others by he way - designed with 2 sideband filters and 1 Xtal ( 9MHz ) rather than todays set of 1 sidebandfilter and 2 Xtals (SSB) or 3 including CW? Was it a problem then shifting VFO without loosing stability? 73, Pierre - F3WT Le 20 déc. 05 à 15:24, Garey Barrell a écrit : Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Karl - The bassy and hissy audio on the sidebands indicates the Carrier Oscillator is off frequency. Normally, the two filters form a letter M, with the Carrier Oscillator in the middle. As the carrier moves to one side of 9.000 MHz, the audio response goes bassy on USB and hissy on LSB. If the carrier moves the other way, then the bassy and hissy are reversed. Do you have an accurate frequency counter? Or a modern digital readout transceiver? The Carrier Oscillator should be on 9.000 MHz in the non -X mode and approximately 9.001 MHz in the -X mode. If it is NOT, and cannot be set to frequency by adjusting C130, then you likely have a bad crystal. If it is, or if it can be set to 9.000 MHz by adjusting C130, then tune in a stable CW signal on any band. This signal could be another transmitter loaded into a dummy load, etc. Tune slowly through this signal while watching the S meter. The meter should show no signal, then rise rapidly, then stay relatively constant for about 2.5 kHz, then drop rapidly as you tune through the signal. Do this in both sideband positions. If the S meter reading does not follow this pattern as you tune through a signal, (may stay up less than 2.5 kHz, or may have a dip in the center,) then you likely have a bad filter. Filters from parted out units show up on EBay from time to time, BUT may also be bad. The INRAD filters are excellent, but they are $100 each, which doesn't make much sense in a $250 transceiver unless it has sentimental value! 73, Garey - K4OAH Atlanta Drake C-Line Service Manual http://www.k4oah.com Karl Corder wrote: I have tried adjusting the balanced modulator and the carrier (c130)and neither one will allow the sideband switch in the X position to give me any drive at all beyond the .1 miliamps. With the sideband switch in the NON X position I can get drive and adjust the resting drive current to the .15 as they recommend. I cannot get equal noise pitch using the C130. As long as the sideband switch is in the NON X position and the other switch is in the X- CW position I can get drive but as soon as I put the ssb switch in the X position there isn't any drive from the rf gain control. Does this mean that one or both of the ssb filters have croaked? I can hear (make out signals in the lower sideband but they are poor and hard to tune in the audio isn't good at all, it is bassy and the usb mode is Hissy( can't change it to bassy or bassy to hissy). Appreciate any recommendations? Karl Corder wa20vj -- Submissions:drakelist@www.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 -- -- Submissions:drakelist@www.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] Tr-4 problem again
Robert Donnell [EMAIL PROTECTED] made an utterance to the drakelist gang -- I feel like the two-filters in the transceivers was a continuation of the theme of the 2A/2B receivers, where changing sidebands was actually moving the filter response, with respect to the BFO. You've all probably seen some of the rigs from other makers, with a single filter and analog VFO. When you changed sidebands, you had to either use a different tuning mark, or recalibrate against the 100 kHz crystal, to account for the carrier being shifted about 3 kHz between upper sideband and lower sideband. With Drake rigs this was not necessary, since the carrier oscillator stayed put. The first Drake transceiver I owned was a TR-3, and I felt like the dual filters gave the radio an upscale flavor, in addition to the potential for improved frequency stability in the local oscillator, because the only time it changed frequency was when it was shifted into the passband for CW transmission. Shifting the carrier frequency instead of using (and switching) a second crystal was undoubtedly a cost saving measure, probably to offset the cost of a second filter, and perhaps to save from having to build potentially less-reliable or less-stable real-time crystal switching. Also, shifting the VFO, to compensate for shifting the carrier oscillator, would have been virtually impossible to make track over the full range of the VFO, without having a second slug-tuned inductor to either swap between, for sideband changes, or to offset the VFO the proper amount at all points in the tuning range, when the alternate sideband was selected. That sounds like my idea of a technician's nightmare. I'm betting just getting one slug-tuned inductor to track a 12% frequency range change with linear frequency change vs. slug insertion was not trivial to learn how to do. In any event, I thought the dual-filter arrangement more elegant than the alternative. 73, Bob, KD7NM -- Original Message -- From: F3WT [EMAIL PROTECTED] Date: Tue, 20 Dec 2005 22:26:05 +0100 F3WT [EMAIL PROTECTED] made an utterance to the drakelist gang -- Hi Garey, Very clear explanation below! I have a related question I was wondering about for a while: Why were TR4s - and others by he way - designed with 2 sideband filters and 1 Xtal ( 9MHz ) rather than todays set of 1 sidebandfilter and 2 Xtals (SSB) or 3 including CW? Was it a problem then shifting VFO without loosing stability? 73, Pierre - F3WT Sent via the WebMail system at webmail.pioneernet.net -- Submissions:drakelist@www.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 --
[drakelist] dirty bandswitches - how to fix?
Jason Buchanan [EMAIL PROTECTED] made an utterance to the drakelist gang -- hi, I've got a Drake R-4B in need of cleaning on the bandswitches. I have to wiggle the bandswitch knob CW/CCW to get the sensitivity that I am expecting. On the 25kc calibrator I can see a 2 S unit difference between just turning it to the 40 or 20m band, or wiggling it until it comes up. Anyone have any suggestions how to go about cleaning the bandswitch? thanks! 73 jason N1SU -- Submissions:drakelist@www.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 power output saga continues...
Robert Donnell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Old engineering axiom: Oscillators Amplify and Amplifiers Oscillate Engineers get the big bucks for solving these problems :-) 73 and happy holidays to all! Bob, KD7NM -- Original Message -- From: Floyd Sense [EMAIL PROTECTED] Reply-To: Floyd Sense [EMAIL PROTECTED] Date: Tue, 20 Dec 2005 17:31:43 -0500 --- most stuff deleted --- Floyd Sense [EMAIL PROTECTED] made an utterance to the drakelist gang -- That may make some sense to the engineers in the crowd, but it caught me by surprise. 73, Floyd - K8AC Sent via the WebMail system at webmail.pioneernet.net -- Submissions:drakelist@www.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] dirty bandswitches - how to fix?
Jason: Try to find a pencil eraser stick. They look like a standard pencil but they have an eraser core.These eraser sticks are gettingharder to find these days. You will find that with plenty of light and some reading glasses (needed by age 54) that you will be able to slowly clean each section of the entire band switch assembly. You must do this very carefully becauseyou can just do a small section of the contact ring on each wafer switch at a time as you progress along. You will have to turn the band switch a little at a time to gradually work your way around the entire ring as you clean it with the pencil eraser stick.You will have to go in at different spots on the contact ring. Work carefully and don't bend any of the switches contact wipers. Keepthe eraser stick fairly sharp so the eraser is protruding a little beyond the wooden portion of the pencil stick. With a little patience you will be able to clean about 98% of the band switch. AfterwardsI always spray a littleCraig Pro-Gold into a plastic lid, then Icarefully lubricate theband switch contact rings with this lubricant. The best thing I have found to apply the contact cleaner /lubricant with is a paper match stick held with a pair of hemostats or needle nose pliers. I justI dip the torn off end of the paper match stick into the cap with the lubricant and it will wick up some of the Lubricant, then you can gently paint it on eachband switch wiper ring and contacts. Do each switch one at a timewhile working the band switch back and forth. DO NOT SPRAY the band switches as the wafer material will absorb the lubricant and that helpsaccelerates their failure. Drake always warned us about spraying the band switches. You can also apply this same lubricant with a small needle applicator. In sure you willreceive no less than a dozen different ways of cleaning these band switches. The way I just describedhas always worked 100% for me every time and I have cleaned many Drake band switches over the years. Not to mention thatyou will end up with a neat job. 73, Don WA9TGT / Don Garrett / Muncie, IN ARCI #6447, ARS #1717, AmQRP, ECI-QRP #001 (Indiana)Drake 2B, R4A, R4B, K2 #3186, K1 #1806 LDG Z-11 Auto Tuner, 102' CF Zepp using glass doobies!
[drakelist] R-4C Audio Problem
Bill Jackson [EMAIL PROTECTED] made an utterance to the drakelist gang -- Greetings, I am working on an R-4C with a strange audio problem. When I rotate the volume control between the 9 and 11 o'clock positions, I hear a faint birdie oscillation at a couple of different spots on the 10m band. The frequency of the oscillation will change with the position of the volume control. Also, when I use a pair of headphones, I hear a distinct change in the quality of the audio in the same range of the volume control that produces the birdies. Any suggestions on what to look for? Thanks de Bill, K9RZ -- Submissions:drakelist@www.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 --
