superstar 3900 2008 model clarifier issue

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silverfox
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superstar 3900 2008 model clarifier issue

Post by silverfox »

hi folks;
just purchased the new model superstar 3900 with the ept360015c chassis.
the problem i have is when on ssb with the coarse clarifier at 12 oclock i am off frequency to others, but if i turn the clarifier a tiny bit to the right just on the notch i am on frequency?
is there any adjusments i can make to enable to be on frequency with the clarifier at 12 oclock or to remove the notch from the clarifier control or if i was to purchase a volume/squelch control to replace the fine/coarse would this have the full 5kc shift either way?
any suggestions would be appreciated.
thanks.....john. :D
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The Defpom
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Post by The Defpom »

You can do some alignments, if you have an external frequency counter to use to test the radio with.

When you say off frequency, is it the TX/RX that is off, of is it just the built in counter ? the counter has an adjustment on it too, which sometimes needs adjusting if it is off a bit.

The alignments are probably much like the normal 3900, so take a look on the site as it should be there.
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Post by zodiac »

With the KC shift set in the notch and the clarifier lined up with it you should be on frequency. All 3900's don't line up spot on 12 o'clock like the old 148 GTL DX there slightly off the 12 o'clock position, that's normal for the 3900.
Dave.
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Twice it's length from halfway.
silverfox
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Post by silverfox »

hi,
on every 3900 ive used the coarse clarifier sits just to the left of the 12 oclock position before the notch engages-on the 2008 model the clarifier has to sit on the notch to be on frequency,this model has no built in frequency counter.what adjustment do i have to make to enable center-frequency with the clarifier at its normal 12 oclock position bearing in mind the coarse clarifier adjusts both rx/tx at the same time?.
the chassis no. is ept360015c-im not aware of any other radio that uses this board.
thanks again....john.
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Rick
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Re: SS3900 2008 model clarifier issue.

Post by Rick »

If it is a case of RX being, off with respect TX, check R136 it should be 10K and R137 it should be 1K, in some radio the resistor R136 is 1K and R137 is 10K, if this is the case just swap the R around and realign the PLL section.

My Sch diagram is on CBTricks
http://www.cbtricks.com/radios/crt/ss_3 ... 00_sch.pdf

If the radio is new, why not just send it back to get the work done under warranty
Rick.
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Post by vintagetech »

I may be misunderstanding the real issue here but my take on this is that you probably just need to make the fine clarifier control track on both receive and xmit. "IF IT DON'T ALREADY" once you do that the alignment for making this unit settle on a specific frequency is just a matter of very minor alignment of the carrier oscillator which will still be the case even if the you don't make the fine clarifier track. if memory serves me this would be l26,27 & 28 AM USB LSB in that order. It's fine to use a counter for the AM alignment but it probably isn't even needed in this case what you really want "I Think" is for the SSB To be more closely aligned with the clarfier controls on center. If you have access to a frequency standard you can count on being right like maybe a friend with a properly working Kenwood or ICOM or something along these lines of quality SSB rigs just put the 3900 on a dumb load place the kenwood or icom's frequency display to say 27.405.00 while on LSB/USB and monitor the audio with a set of quality headphones while adjusting L27 and L28 for the most natural voice response you can. remember you may have to attenuate the Kenwoods or Icom's receiver to lower it's sensitivity or put the kenwood/Icom on a dumb load as well as long as you are on bench setup I have aligned many thousands of SSB rigs in this way against my 430s kenwood and never have been unhappy with the results and my customers really enjoy being able to hear DX stations running kenwoods and icoms telling them they are right on frequency. Just remember being right on frequency doesn't require that the clarifier be in the 12Oclock position being right on means both you and the person you are talking to are telling each that you sound great. So even though it's nice to be able to put the control on center and know that it's there it won't very often result in not being forced to move it to compensate for all the radios that are not on what you call center. But this is one way of doing it there are more technical methods of accomplishing this and there are times when more advanced methods are required but this isn't one of them, at least I don't think it is. but this works really well.

And please don't hesitate to inform me if I'm completely off base I'm not at all with issue of anyone setting me straight. besides I need the chance to revise and extend my remarks in an effort defend my mistakes.

Dennis
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Rick
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Re: SS3900 2008 model clarifier issue.

Post by Rick »

Dennis, the SS3900 is a radio with history of frequency drift problems and with your method, you will just chase you tail.

It is best just let someone with a good knowledge of the type of chassis set it up.

Since SS3900 first can on the seen, I must have converted and serviced well over 800 of them and when I do the conversion to get them on 11meters I also change some components in the loop mixer and carrier osc.

From S/N M80100800 to M80101800 the resistors R136 and R137 are fitted the wrong way round.
This affects the loop mixer and makes it very hard to get the clarifier just right.

Rick (Euro Radio Co).
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Post by vintagetech »

I'm well aware of problems you speak of but it didn't sound like this radio was drifting it just sounded like it didn't line up on 12 oclock position with other radios he may have been trying to talk to. I must have missed the drifting complaint and that is possible. I will read all the postings again. He said this was a brand new radio and although it could fall within the serial number range you speak of I still was not getting the idea that the radio had a drift problem not from what the gentleman was saying. I have only serviced about 60 thousand radios in the last 39 years but I will admit I don't think more than a few hundred 3900's so you do have me beat there. I will pay closer attention to the complaints and try to question them more closely as I do whenever someone brings a radio in our shop. Thanks Rick

Dennis
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Post by James Unit 198 »

I have had 2 CRT SS3900 and both had the trouble with the clarifier.
The clarifier is always a bit of and u need to keep adjusting has the radio warms up. My last one which sorted out by Rick is ok and has been for the past 2 years and is used every day mobile.

I have known Rick for over 20 years.
I would trust him as I know that his work is to a very high standard. He his not the cheapest but in this world you get what you pay for.
He has been repairing ham and cb radios for over the pasts 38 years for most of the dealers in the UK and some in Europe.
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dxswe
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Post by dxswe »

I had also own a SS 3900 CRT and the clarifier problem was the same with that radio.I used galaxy 77 hml service manual to realign my radio.The pcb board its very like the 3900 board.After my realignmemt the radio was much better.More stable on the ssb band.


Rick is a very good tech.He had help with my galaxy dx 2517.Thank for that Rick :D


http://www.cbtricks.com/radios/galaxy/dx77hml/index.htm
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