[TenTec] Argosy II 525D carrier oscillators

Clark Savage Turner WA3JPG turner@safety.ics.uci.edu
Sat, 14 Mar 1998 17:56:25 -0800

First, Peter, your return address hasn't worked for me in two tries.  
Pretty frustrating.  Could you try to give me another one?  I did 
remove the "no spam" stuff and it still won't go.  I will try this 
post to the list, hope it is of general interest.

> I have an Argosy II here for a 'test drive' with a view to buying it but
> there is, I think, a problem with the setting of the carrier oscillator.
> I've not (yet) been able to put a frequency counter on it, but have been
> trying to set-up C1, C2 and C3 on the ssb generator board. 

I have been there!  I have seen the mountain and climbed it :-)

> However, there seems insufficient adjustment available on the trimmers.
> At the moment, switching between SB-N and SB-R appears to produce
> Might this be due to an ageing xtal, or could there be another solution?

No, you just need to have a good freq counter and patience to set it
correctly.  There is interaction between the adjustments and they must
be done in order, and then repeated till you get it just right.  Honest,
it worked for me.

> In addition, if I switch into circuit the 217 (500Hz) narrow cw filter
> there are two further problems.  Firstly, when the received signal is in
> the centre of the filter passband, the resultant audio note is very low
> indeed - maybe 250 - 300Hz.  Secondly, there is excessive attenuation
> through the filter - an S9 signal will drop to around S1.

Sounds right, the carrier oscillators need adjustment.  I eventually
got mine so that the 250 Hz filter was centered right where I wanted
it, and got the power output back up to par (that can be affected too!)
so just wait for your freq counter and take your time, it will work
out fine.

Write again if you need more information, I sold my Argosy II, but
recall a lot and still have my manual.  Oh, and the manual may be
in error about which oscillator is which.  I think it is note (4) 
on page 3-18 of the manual, "Set the mode switch to SB-N and adjust C2 ..
should read C3, not C2.  Important to note!

Good luck.


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