To Bob and All,
My Paragon, when I received it. Had 2 Switching
Diodes shorted on the Low Pass Filter Board. This was causing the Radio to
draw Massive Amounts of Current when we tried to Transmit on 40 Meters and
I forget what the other band or bands were. Guess it depends on which Diode
or Diodes are Shorted on the Low Pass Filter Board. We also found that the
Receiver Sensitivity was or seemed to be far below what we thought it
should be. Since these Diodes are a Dime a Dozen. We changed every diode on
the High Pass and Low Pass Filter Boards. Also, Bob the TAX Man, is 100%
Correct about the Receive Only " or what ever the Manual calls it " Switch
that was Dirty. This was NOT a job for Spraying cleaner everywhere. We just
borrowed one of my Miss Brenda's, Insulin Syringes and placed about One
Drop of DeoxIt in the switch while moving said switch back and forth ((
Exercising )) it for several seconds... It has been 4 years now. My Paragon
has called the Wednesday Evening Tennessee Phone Net .. Without Fail ...
for over 3 years. We also had the Dreaded " PLL Out of Lock " Failure when
we first got it, which was cured by a Lot of very delicate cleaning and
re-soldering the connections on the Major and Minor PLL Loop Boards.
Recently, there was a Glitch which would cause the Transmit and Receive to
drop out until the Power Switch was cycled Off and Then On. This happened
mostly when the RF Power was set to High Levels. What we found was, the
replacement of All 4 Capacitors inside the PA Compartment CURED this issue.
Some models have 3 and others have 4 Capacitors. Although it is not really
necessary, we have also fitted a 24 Volt type Computer Fan to the PA Heat
Sink. At half speed/voltage we never hear it run.... or almost never. There
is also a known issue of Capacitor Failures in the Display circuits, we
have never seen that yet but, it is good to know about. Monster Thanks go
out to Paul Clinton (( Ten Tec Service Manager )) Gary (( Ten Tec Service
)) and Bob/K4TAX (( The Tax Man )) Who is not only a Very Nice Guy. Also
one of the Ten Tec Ambassadors. And the True Meaning of the term " Southern
Gentleman " Folks, if any of the 3 guys just mentioned, tells you that it
is Raining Steak, just get the Charcoal out for your Grill.... Because you
will have a Yard Full of Grade A Cow on your Front Lawn Shortly. I am here
for anyone in the group with Practical Experience on the Paragon ( and
other older Ten Tec Gear ) and Bob/K4TAX is the Guru on All of Them. We
have nothing but Praise and Respect for Ten Tec's Legendary Service
Department. Oh Yeah, Paul, at Ten Tec..... just dropped a few of those
needed Diodes into an Envelope and shipped them to me... Free of Charge. I
would like to see the Owner of an YaeComKensu Radio get that kind of
personal advise and help/parts from their Service Department!
Thanks for reading 73 and May God Bless from
Wade/KJ4WS
On Sun, Jul 13, 2014 at 10:36 PM, Bob McGraw - K4TAX <RMcGraw@blomand.net>
wrote:
> Correct and one reason I keep my old Triplet 603 VOM, it has a + & -
> switch on the front, thus I don't have to flip the test probes on the
> device. Of course my FLUKE DVM has provision for a diode test as well.
> But with it I have to flip the leads to measure forward and reverse
> resistance of the diode.
>
> I'd expect some of those diodes on the High Pass Filter board are leaky
> and thus two or more filters may be engaged at once. I find it somewhat
> interesting that 8 diodes were open and all on the input side of the
> filters.
>
> 73
> Bob, K4TAX
>
>
>
>
>
>
>
> ----- Original Message ----- From: "Tony" <va3dwi@gmail.com>
> To: <tentec@contesting.com>
> Sent: Sunday, July 13, 2014 10:11 PM
>
> Subject: Re: [TenTec] Paragon problem
>
>
> A lot, if not most, older VOM meters in resistance mode have the polarity
>> reversed on the probes. Red is negative and black is positive. Keep that
>> in mind when testing diodes.
>> Tony VE3DWI.
>>
>> Sent from my BlackBerry 10 smartphone on the Bell network.
>> Original Message
>> From: Bob McGraw - K4TAX
>> Sent: Sunday, July 13, 2014 14:35
>> To: Walt K8CV; Discussion of Ten-Tec Equipment
>> Reply To: Discussion of Ten-Tec Equipment
>> Subject: Re: [TenTec] Paragon problem
>>
>> Since there are no reed relays, or relays of any type, one would do better
>> to do a DC voltage check of each filter section for each band. This can be
>> done with the RX HP Filter removed but connected to the radio via the
>> ribbon
>> connector. This way the radio can switch bands and one can measure to
>> confirm switching is taking place by measuring the voltage across each of
>> the 16 diodes. There's 16 of them as indicated on the schematic.
>>
>> Out of the radio and no power applied, each diode can be accurately
>> checked
>> for forward and reverse resistance with an ohm meter with a suitable diode
>> test feature. Or use one of the old fashion VOM type meters.
>>
>> One other note, be mindful if the issue exists on all bands or just one or
>> two bands. The switching voltage can be observed on connectors #16 and
>> #14.
>>
>>
>> 73
>> Bob, K4TAX
>>
>>
>> ----- Original Message ----- From: "Walt K8CV" <waltk8cv@wowway.com>
>> To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
>> Sent: Sunday, July 13, 2014 7:41 AM
>> Subject: Re: [TenTec] Paragon problem
>>
>>
>> Have you changed the reed relays or talked to TenTec about them? A stuck
>>> /
>>> pitted transmit reed will suck off the receive.
>>>
>>>
>>>
>>> Walt K8CV
>>> -----Original Message----- From: Vic Klein
>>> Sent: Sunday, July 13, 2014 6:34 AM
>>> To: tentec@contesting.com
>>> Subject: Re: [TenTec] Paragon problem
>>>
>>> Thanks for the suggestions. A few days of sleuthing and talking to Garry
>>> at
>>> Ten Tec led me to discover that all the input (D1-D8) switching diodes on
>>> the Hi-Pass filter board (81330) were "open". Garry said In4148's could
>>> be
>>> substituted, which I did, and now all the sections seem to test OK and
>>> switch appropriately...but the same symptoms remain: all functions seem
>>> normal, but sensitivity is off by around 4 S-units. None of the RF chokes
>>> seem to be open, and bypassing the Lo-pass FX board by selecting the
>>> external receive antenna makes no difference. I am looking at the 1st
>>> Mixer
>>> now, although I do get the appropriate 20dB reduction when switching in
>>> the
>>> attenuator, which shuts off the RF stage, so I am still befuddled.
>>>
>>> One anomally I see is the the voltages on the band switching diodes seems
>>> a
>>> bit low. I would have expected a lower voltage at D1 as it has more
>>> resistance in the path, but the reverse is true and it reads about 9.4v
>>> as
>>> opposed to the other 7 Hi-pass sections at about 7.25v when selected.
>>> That
>>> still seems plenty to bias the diodes and pull in the low-pass relays,
>>> but
>>> curious.
>>>
>>> =Vic=
>>> WA4THR
>>> ____________________________________________________________
>>> To: Discussion of Ten-Tec Equipment <tentec@contesting.com>
>>> Subject: Re: [TenTec] Paragon problem
>>> From: Wade Staggs <tvman1954@gmail.com>
>>> Reply-to: Discussion of Ten-Tec Equipment <tentec@contesting.com>
>>> Date: Wed, 9 Jul 2014 17:39:05 -0500
>>> List-post: <tentec@contesting.com">mailto:tentec@contesting.com>
>>>
>>> *Far from being an Expert myself, The first place I would look would be
>>> the
>>> RX High Pass Filter Board ( 81330 ) At the Antenna Input to the High Pass
>>> Filter Board, there are two LC Coils and a Diode ... Any of which could
>>> be
>>> Shorted or open in the case of the LC Coils. You should be able to inject
>>> signal or an antenna input on each side of the High pass Filter Board. I
>>> would use a Clip Lead and touch my Antenna to the output connection from
>>> the board and see what happens. The High Pass Filter board uses Switching
>>> Diodes to select the correct Filter for each Band. I am believing that
>>> like
>>> Ivory Soap, 99 44/100s percent sure that the problem is somewhere on the
>>> High Pass Filter Board.*
>>> * 73 and May God Bless from
>>> Wade/KJ4WS*
>>>
>>>
>>> On Wed, Jul 9, 2014 at 5:20 PM, K8JHR <jrichards@k8jhr.com> wrote:
>>>
>>> Hi Vic -- I am far from expert on this, but I wonder if you can locate
>>>> ANOTHER protective diode in the receiver circuit. I once killed my Omni
>>>> VII receiver by hot-switching an "active" receive only antenna - the
>>>> power
>>>> connector arced to case ground of a bias-tee injector as I plugged it
>>>> in,
>>>> and that fritzed the receiver. Gary at TenTec service called me to
>>>>
>>> explain
>>>
>>>> it before he fixed it, and I believe he said there were multiple diodes
>>>> to
>>>> protect the rig in such cases.
>>>>
>>>> So... perhaps you have more than one diode or fuse or other prophylactic
>>>> device to check?
>>>>
>>>> -----------------------------K8JHr ------------------
>>>>
>>>
>>> _______________________________________________
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>>> http://lists.contesting.com/mailman/listinfo/tentec
>>>
>>>
>>
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>
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