Bob,
I resoldered all the connections on both the Minor and Major Loop PLL boards
(whew..what a job!!) but when I put it all back together, it STILL would not
go back in lock. I then did your trick below of tweaking the small trim pot
on U2 on the Major Loop board, and it went back into lock!!!!
73 and thanks a LOT, my friend!!!!
Mike
Michael W. Woolverton, MSG, USAF (Ret.)
SV0AC/WB0ZPW
sv0ac@otenet.gr
----- Original Message -----
From: Robert Weingaertner <weingaertner@nac.net>
To: Mike Woolverton <sv0ac@otenet.gr>
Cc: <tentec@contesting.com>
Sent: Friday, April 16, 1999 04:16
Subject: Re: [TenTec] Paragon "PLL Out of Lock"
> 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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