Mike,
This is a common problem with the Paragon I. The cure is to remove
the topside shield cover (where the FM adapter goes), take out the
major loop PLL board and resolder all of the connections. The problem
is usually caused by cold solder joints. There are 4 VCO's on the
board, so if you can localize the porblem to one range of frequencies
you might be able to resolder the connections in that area only.
However, I ended up resoldering everything.
Pressing on the board or flexing it can sometimes cause the problem.
Other symptoms are distorted received SSB signals or warbly CW tones.
Also check the VCO for each band. There is a test point at the junction
of Q1-C and Q3-C. The test point voltage will range from about 2.8 V
to 7.6 V DC fron the low to the high end of the VCO range. You can tweak
the slugs in the VCO cans to alighn them. Count the
VCO shield cans from left to right when loooking at the board
with the rigs front panel facing you. The VCO ranges are a follows:
1. 22-30 MHz
2. 14-22 MHz
3. 7.0-14 MHz
4. .1-7.0 MHz
VCo's are selected by voltages on connector 90 (left to right 1,2,3,4).
Each connector pin will go to 0 V when that VCO is selected. The pins
corresponding to the unselected VCO will remain at 5 V.
In some cases you may need to resolder the connections on the minor
loop board. This is tedious, because the shield on the bottom of the
board has to be unsoldered and removed to get at the connections. If
you do this, save yourself a repeat operation by esoldering the
entire board.
I found that some of the little transformers, the ones with the ferite
cores an colored wire wound through them, were microphonic when I
poked at them. The cure was to flow some clear nail polish into them.
Q-dope or epoxy should also work well, provided it can flow into the
holes in the core. Some of the aluminum electrolytic capacitors
were also microphonic. I replaced them with tantalum types.
Lastly, and maybe you should try this first, some Paragons had a
tiny trim pot on U3 on the major loop board. THis pot is sensitive and
a small rotation will cause the PLL to go in and out of lock. Adjust
the pot for a voltage of 3.2 V at the wiper, or set it to the middle
of its lock range. The second thing to try is VCO alignment, but
don't be surprised if you have to resolder all of the connections
on the board anyway.
I know this sounds like a lot of work, but I had to do it all (I like
tinkering anyway). I was rewarded, though. After putting in all of
these fixes, my Paragon has been reliably playing sweet tunes again,
and I'm keepin' it!
73, Bob WB2VUF
> Mike Woolverton wrote:
>
> Hello all and greetings from sunny Athens, Greece!!
>
> I am the proud owner of a Model 585 Paragon, which I bought
> re-conditioned from the factory a few years ago. Yesterday, the
> display suddenly started flashing "PLL OUT OF LOCK," along with the
> frequency I was on at the time. I turned the rig off for awhile, then
> back on and all seemed to work fine. I didn't give it another thought
> until this afternoon when about a minute after I turned the rig on, it
> went out of lock again. I performed a re-set, hoping this would clear
> up the problem, but it didn't. Since it is no small matter to return
> the rig to Ten-Tec for service (due to exorbitant mail costs, Customs,
> etc), does anyone have any suggestions??
>
> Thanks and 73
>
> Mike
> Michael W. Woolverton, MSG, USAF (Ret.)
> SV0AC/WB0ZPW
> sv0ac@otenet.gr
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