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TomJoad
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Post subject: Transoceanic 7000 problem Posted: Mar Sun 18, 2012 9:34 pm |
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Joined: Mar Sun 11, 2012 2:24 am Posts: 112 Location: 100 miles west of DC
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Hi All:
I got this thing over a month ago and it worked very well until now. I think it's a 7000Y-1 as the last copyright date in the pull out log is 1971. It was a great performer except when using the BFO on SSB where the RF gain needed to be backed down on strong (ham) stations to avoid distortion. But the real problem is the other day I lost operation. It turns on and you hear the normal noise floor like the amplifier section is OK but there is basically no reception. I say basically because from time to time the strongest station on the SW or BC band may be barely audible when the volume is at max. So I don't expect anyone to know for sure where to point me but perhaps there is a common problem with these that a Transoceanic regular may be aware of. I found the info at nostalgia but I figured I might gain some insight from someone who has been down this road before where I have not.
ET
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Brett_Buck
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Post subject: Re: Transoceanic 7000 problem Posted: Mar Sun 18, 2012 10:13 pm |
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Joined: Aug Wed 24, 2011 4:35 am Posts: 1272 Location: Sunnyvale CA
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TomJoad wrote: Hi All:
I got this thing over a month ago and it worked very well until now. I think it's a 7000Y-1 as the last copyright date in the pull out log is 1971. It was a great performer except when using the BFO on SSB where the RF gain needed to be backed down on strong (ham) stations to avoid distortion. But the real problem is the other day I lost operation. It turns on and you hear the normal noise floor like the amplifier section is OK but there is basically no reception. I say basically because from time to time the strongest station on the SW or BC band may be barely audible when the volume is at max. So I don't expect anyone to know for sure where to point me but perhaps there is a common problem with these that a Transoceanic regular may be aware of. I found the info at nostalgia but I figured I might gain some insight from someone who has been down this road before where I have not. I haven't been down this particular road but lots of others. Does it work on FM/VHF? And when you tune around on, say, BC, does the signal strength meter move as if it was still tuning things but you just couldn't hear it? If it works on FM but not AM (SW/BC/Longwave) then it's something in the AM RF section. If it doesn't work on AM or FM, I would look into the IF or audio driver sections. The usual issues, however, are dirty switches, unseated transistors, or failed capacitors. Clean the bandswitch and other switches carefully with DeOxit D5, remove and reseat every transistor. If that doesn't work try the test below, but I would be looking at capacitors at that point. You can test the audio section by setting the band selector "between" bands, and then playing an iPod through the tuner output. If that doesn't work then thats a very good indication that there is something wrong in the audio section. You can learn a lot from voltage measurements as shown on the schematic, too, but you can also get fooled because they aren't exact. I am a relative newbie but I have worked on many of the transistor transoceanics. The collective knowledge of the people here is truly amazing. Post more symptoms and the results of the troubleshooting tests and I can guarantee someone here can figure it out. Brett
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Dave Doughty
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Post subject: Re: Transoceanic 7000 problem Posted: Mar Mon 19, 2012 2:43 am |
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Joined: Jan Thu 01, 1970 1:00 am Posts: 13665 Location: Utica, NY 13502 (USA)
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As has been discussed in many times in this section, besides dried out electrolytic caps, this model is plagued by a certain series of .05 uf disc ceramic caps that have either shorted or show leakage. It is unusual for this to happen with most disc caps but, in this case, many examples in the Royal 7000 series have had this problem. Unfortnately, there are a lots of caps of this type used in this radio.
Dave
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Jetercreek
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Post subject: Re: Transoceanic 7000 problem Posted: Mar Tue 20, 2012 11:17 pm |
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Joined: Jun Fri 03, 2011 3:22 am Posts: 37 Location: S. W. Missouri
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Dave Doughty wrote: ...this model is plagued by a certain series of .05 uf disc ceramic caps that have either shorted or show leakage.
Dave Interesting! I learned that years ago before the Web and didn't realize it was common to the model. I let some miscreant over in the TV forum talk me out of that radio many years ago, but as I recall: Checking the A+ lead on the I.F.'s showed a short and there was a single 50 volt disk that could have caused that. It WAS the culprit. The cap lived below the dial and was very difficult to get to. I no longer can find the schematic, but have the same problem with most other things. AM/SW was dead. FM still worked on that one.
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TomJoad
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Post subject: Re: Transoceanic 7000 problem Posted: Mar Wed 21, 2012 1:28 am |
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Joined: Mar Sun 11, 2012 2:24 am Posts: 112 Location: 100 miles west of DC
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Thanks folks for the replies. The first thing I checked was FM and its dead too. I also checked the signal meter on the couple of barely audible signals and it was at the resting position. The problem appeared after I had left it on a day or two. I guess I'll go start looking and see what I can see so to speak.
ET
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Brett_Buck
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Post subject: Re: Transoceanic 7000 problem Posted: Mar Wed 21, 2012 2:44 am |
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Joined: Aug Wed 24, 2011 4:35 am Posts: 1272 Location: Sunnyvale CA
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TomJoad wrote: Thanks folks for the replies. The first thing I checked was FM and its dead too. I also checked the signal meter on the couple of barely audible signals and it was at the resting position. The problem appeared after I had left it on a day or two. I guess I'll go start looking and see what I can see so to speak. I am thinking IF string. Time to start checking those voltages. Brett
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PBPP
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Post subject: Re: Transoceanic 7000 problem Posted: Mar Wed 21, 2012 4:05 am |
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Joined: Jun Tue 21, 2011 8:27 pm Posts: 2087 Location: Virginia
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Hi Tom,
Welcome to the ARF forums!
I have an original service manual for your radio (D7000-Y) and have scanned it. Would you like a copy? If so, PM me with your e-mail address or I can print it out and send it to you via snail mail. Either way works for me.
~ Mitch ~
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Jetercreek
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Post subject: Re: Transoceanic 7000 problem Posted: Mar Sat 24, 2012 4:21 pm |
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Joined: Jun Fri 03, 2011 3:22 am Posts: 37 Location: S. W. Missouri
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TomJoad wrote: I also checked the signal meter on the couple of barely audible signals and it was at the resting position.
ET OK. I have a closet full of stupid questions I need to get rid of: You did re-seat the transistors, right?
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Tim Tress
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Post subject: Re: Transoceanic 7000 problem Posted: Mar Sun 25, 2012 3:40 am |
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Joined: Jan Thu 01, 1970 1:00 am Posts: 5763 Location: Beaver Falls, PA. USA
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Mitch, I could use a copy of the scan as well. Thanks in advance!
_________________ Tim KA3JRT
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PBPP
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Post subject: Re: Transoceanic 7000 problem Posted: Mar Sun 25, 2012 5:19 am |
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Joined: Jun Tue 21, 2011 8:27 pm Posts: 2087 Location: Virginia
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Tim Tress wrote: Mitch, I could use a copy of the scan as well. Thanks in advance! It's on it's way.... Prolly scanned it at too high a resolution so they will be huge files. ~ Mitch ~ EDIT: Just tried sending those files. Waaaay too huge. Will have to resize and resend. Give me a day or so to get back to the house. I'm at the gf's abode doing a major honeydoo. <headache> ~ M ~
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TomJoad
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Post subject: Re: Transoceanic 7000 problem Posted: Mar Sat 31, 2012 7:54 pm |
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Joined: Mar Sun 11, 2012 2:24 am Posts: 112 Location: 100 miles west of DC
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Jetercreek wrote: TomJoad wrote: I also checked the signal meter on the couple of barely audible signals and it was at the resting position.
ET OK. I have a closet full of stupid questions I need to get rid of: You did re-seat the transistors, right? Actually I still haven't even opened it up yet........I will soon, thanks for the tip ET
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TomJoad
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Post subject: Re: Transoceanic 7000 problem Posted: Mar Sat 31, 2012 7:56 pm |
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Joined: Mar Sun 11, 2012 2:24 am Posts: 112 Location: 100 miles west of DC
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PBPP wrote: Hi Tom,
Welcome to the ARF forums!
I have an original service manual for your radio (D7000-Y) and have scanned it. Would you like a copy? If so, PM me with your e-mail address or I can print it out and send it to you via snail mail. Either way works for me.
~ Mitch ~ Mitch: Thanks so much for that. An email will do. You can send it to etbmwva"at"aol"dot"com - again thanks much! ET
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PBPP
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Post subject: Re: Transoceanic 7000 problem Posted: Mar Sat 31, 2012 11:16 pm |
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Joined: Jun Tue 21, 2011 8:27 pm Posts: 2087 Location: Virginia
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Hi Everybody, I apologize for not sending/emailing the R7000Y Schematic/Service Manual. Had it scanned in at 1200 dpi and the files are HUGE. Keep meaning to resize and resend them, but something keeps coming up. I'll be sure to get 'er done this weekend. ~ Mitch ~
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DragonForce
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Post subject: Re: Transoceanic 7000 problem Posted: Apr Wed 11, 2012 4:36 am |
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Joined: Feb Sun 05, 2012 3:41 pm Posts: 315 Location: Bristol, SW England
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I've had a similar problem to this on an old AM CB radio set - and yeah, it was solid state.
Basically, the RF gain control pot had broken. I replaced the pot and things were fine again - just wondering if this could be the cause since you mentioned that you had to twiddle with the RF gain to stop distortion on high level signals.
_________________ I smell smoke.....
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TomJoad
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Post subject: Re: Transoceanic 7000 problem Posted: Apr Sat 14, 2012 5:44 am |
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Joined: Mar Sun 11, 2012 2:24 am Posts: 112 Location: 100 miles west of DC
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Took the back off finally. Wild how the transistors are "mounted" in sockets for easy access. I'd said an old tube guy decided on that design. I started thinking and the fact the problem started after it was left on (75 meters) for a couple of days might give a clue. I'm a ham and may have transmitted near that band ( on 80M) with about 600 watts sideband and the antenna is only about 120 feet away. May have harmed the front end somewhere. I hope I can get the schematic from that poster above. No rush. Thanks again all.
ET
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Brett_Buck
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Post subject: Re: Transoceanic 7000 problem Posted: Apr Sat 14, 2012 5:54 am |
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Joined: Aug Wed 24, 2011 4:35 am Posts: 1272 Location: Sunnyvale CA
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TomJoad wrote: Took the back off finally. Wild how the transistors are "mounted" in sockets for easy access. I'd said an old tube guy decided on that design. I started thinking and the fact the problem started after it was left on (75 meters) for a couple of days might give a clue. I'm a ham and may have transmitted near that band ( on 80M) with about 600 watts sideband and the antenna is only about 120 feet away. May have harmed the front end somewhere. I hope I can get the schematic from that poster above. No rush. Thanks again all. I am sure I have one, if that's the only issue. Send me a n email at buckbw AT pacbell DOT net with the Chassis number (just to be sure you get the right one) and I will send you the right service manual. Brett
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PBPP
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Post subject: Re: Transoceanic 7000 problem Posted: Apr Sun 15, 2012 8:43 am |
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Joined: Jun Tue 21, 2011 8:27 pm Posts: 2087 Location: Virginia
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My apologies to all for not getting the manual/schematic scanned. 400 dpi makes the schematic readable, but I have to 'paste' the individual scans together because its a fold-out schematic.
When scanning a 400 dpi and stitching it all together, the final file size is still too huge to send, which is the reason for the delay.
Gonna have to play around with the scanning and find a compromise.
~ Mitch ~
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Brett_Buck
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Post subject: Re: Transoceanic 7000 problem Posted: Apr Mon 16, 2012 12:13 am |
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Joined: Aug Wed 24, 2011 4:35 am Posts: 1272 Location: Sunnyvale CA
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PBPP wrote: My apologies to all for not getting the manual/schematic scanned. 400 dpi makes the schematic readable, but I have to 'paste' the individual scans together because its a fold-out schematic.
When scanning a 400 dpi and stitching it all together, the final file size is still too huge to send, which is the reason for the delay.
Gonna have to play around with the scanning and find a compromise.
~ Mitch ~ If there was some place for me to post them, I would do that, since I already have them just sitting on my hard drive. Brett
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Dave Doughty
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Post subject: Re: Transoceanic 7000 problem Posted: Apr Mon 16, 2012 3:00 am |
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Joined: Jan Thu 01, 1970 1:00 am Posts: 13665 Location: Utica, NY 13502 (USA)
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