TenTec
[Top] [All Lists]

Re: [TenTec] Paragon Reference Oscillator

To: Discussion of Ten-Tec Equipment <tentec@contesting.com>, Discussion of Ten-Tec Equipment <tentec@contesting.com>, Bob McGraw K4TAX <rmcgraw@blomand.net>
Subject: Re: [TenTec] Paragon Reference Oscillator
From: Pete Ferrand <petef@sprynet.com>
Reply-to: Pete Ferrand <petef@sprynet.com>, Discussion of Ten-Tec Equipment <tentec@contesting.com>
Date: Sun, 25 Oct 2020 19:17:57 -0500 (GMT-05:00)
List-post: <mailto:tentec@contesting.com>
Thanks for responding you guys but I don't think you understood what I'm saying.

I can't leave the reference oscillator at 84 MHz because it's not at 84 MHz! 

The best I can do is adjust it to 300 Hz lower in frequency than 84 MHz. The 
specs call for plus/minus 5 Hz. I thought this was clear.

Why do you guys want me to start with the BFO adjustments? 

I've aligned dozens of Ten-Tecs and I've always followed the Ten-Tec alignment 
procedures, which call for starting by setting the reference oscillator.

It seems absurd to tune the BFOs when the reference oscillator is off 
frequency!!!

Hence, I need to simply add frequency to the crystal. About 200 Hz would do it.

This is the problem. When the reference is correct the rest of the 
USB/LSB/CW/FM tuning is perfectly fine. But the reference oscillator can't be 
put on frequency.



Thanks.
Pete













-----Original Message-----
>From: "Bob, WB2VUF via TenTec" <tentec@contesting.com>
>Sent: Oct 25, 2020 6:20 PM
>To: Discussion of Ten-Tec Equipment <tentec@contesting.com>, Bob McGraw K4TAX 
><rmcgraw@blomand.net>
>Cc: "Bob, WB2VUF" <wb2vuf@verizon.net>
>Subject: Re: [TenTec] Paragon Reference Oscillator
>
>I agree. Leave the reference oscillator exactly at 84 MHz and align the 
>BFO crystals instead.  They are the most likely to be off frequency.  
>Yes, they must be adjusted in sequence as indicated in the manual.
>
>73,
>
>Bob WB2VUF
>
>On 10/24/2020 11:23 AM, Bob McGraw K4TAX wrote:
>> The first thing to check is the oscillators on the Transmit Audio/BFO 
>> Board.  The procedure is on page 6-65 of the manual. From experience, 
>> the adjustments are somewhat interactive and must be done in the order 
>> as listed.  You should go through the procedure at least twice.  Be 
>> sure the radio has been on for 1 hr to allow the temperature to 
>> stabilize as the crystals are subject to drift with temperature.
>>
>> As to the 42 MHz crystal, it may have aged to the point that it will 
>> not be in the range needed.    Replacement is the most likely option.
>>
>> 73
>>
>> Bob, K4TAX
>>
>> On 10/24/2020 2:54 AM, Peter Ferrand wrote:
>>> I have a new-to-me Paragon 585.
>>>
>>> The rig is slightly off frequency from its readout and the best I can 
>>> do is adjust the reference oscillator with C1 to 300 Hz lower in 
>>> frequency than the 84 MHz it's supposed to be. Ten-Tec specifies this 
>>> frequency must be plus or minus 5 Hz at 84 MHz, which is the output 
>>> of the frequency doubler.
>>>
>>> I tried removing or reducing C2 but the oscillator stops oscillating. 
>>> Rather than track down a new 42 MHz crystal, I wonder if anyone with 
>>> more design skills than I have can suggest a slight redesign of the 
>>> circuit to pull the existing crystal higher.
>>>
>>> Thanks.
>>> Pete
>>> WB2QLL
>>> Mount Pleasant, WI
>>>
>>>
>>> _______________________________________________
>>> TenTec mailing list
>>> TenTec@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/tentec
>>>
>>
>> _______________________________________________
>> TenTec mailing list
>> TenTec@contesting.com
>> http://lists.contesting.com/mailman/listinfo/tentec
>
>
>
>-- 
>This email has been checked for viruses by Avast antivirus software.
>https://www.avast.com/antivirus
>_______________________________________________
>TenTec mailing list
>TenTec@contesting.com
>http://lists.contesting.com/mailman/listinfo/tentec
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
<Prev in Thread] Current Thread [Next in Thread>