[Johnson] Johnson Digest, Vol 92, Issue 10

[Chris]

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>Today's Topics:
>
>   1. Invader 200 Help (ewirtz)
>   2. VIKING I FOR SALE (Dan Cotsirilos)
>   3. Re: Invader 200 Help (David C. Hallam)
>
>
>----------------------------------------------------------------------
>
>Message: 1
>Date: Sat, 17 Sep 2011 13:31:04 -0500
>From: ewirtz <ewirtz at hbci.com>
>Subject: [Johnson] Invader 200 Help
>To: Johnson <johnson at mailman.qth.net>
>Message-ID: <4E74E768.40908 at hbci.com>
>Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
>Hi,
>
>I'm working on a sick Invader 200. First of all I need to find a good 
>T2, the 9MHz Amplifier Tuning transformer, or a suitable replacement. 
>Second if any of you guys know where I can find typical RF voltage 
>measurement data for the 9 MHz amp, 1st mixer etc. I'm sure someone out 
>there has suffered through the same things I am with this worth brute. 
>Any help or advice will be gratefully appreciated. Please don't tell me 
>to trash it instead. Hi!!
>
>73,
>
>Ed, K?BKA
>
>
>
>------------------------------
>
>Message: 2
>Date: Sat, 17 Sep 2011 14:06:01 -0500
>From: "Dan Cotsirilos" <k9dtc at comcast.net>
>Subject: [Johnson] VIKING I FOR SALE
>To: "Johnson" <johnson at mailman.qth.net>
>Message-ID: <FBD5BF65BDC343899CF0DA548A01E6FD at DanPC>
>Content-Type: text/plain; format=flowed; charset="iso-8859-1";
>	reply-type=original
>
>Anyone in the Chicago are interested in a Viking I? This is untested 
>complete in a original cabinet $100.
>
>
>
>
>
>Dan K9DTC
>
>
>
>------------------------------
>
>Message: 3
>Date: Sat, 17 Sep 2011 15:23:05 -0400
>From: "David C. Hallam" <dhallam at knology.net>
>Subject: Re: [Johnson] Invader 200 Help
>To: ewirtz <ewirtz at hbci.com>
>Cc: Johnson <johnson at mailman.qth.net>
>Message-ID: <4E74F399.4060704 at knology.net>
>Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
>Ed,
>
>I have correspondence from Johnson dated 2/20/62 with a slightly 
>modified procedure for adjusting T2.
>
>  * Mode switch to CW
>  * RF level to maximum clockwise
>  * Connect VTVM probe to pin 9 of V3
>  * Short out T5 trimmer with an alligator clip
>  * Adjust the slug of L3 so that the top of the threaded rod is 9/16"
>    above the metal cap of the coil (not the metal ears)
>  * Bottom core of T2 should be at bottom limit of its travel
>  * Run top core pf T2 through the first peak as evidenced on the
>    voltmeter and adjust for peak reading at second peak reached
>  * Adjust bottom core to second peak reached
>  * Readjust top and bottom cores if necessary to obtain maximum reading
>  * A minimum of 1 volt should be obtained at pin 9 of V3 with full RF
>    level control (if balanced modulator had been balanced previously,
>    it will have to be unbalanced)
>  * Remove voltmeter probe
>  * Remove alligator clip from T5
>  * Set trimmer to approximately 35 to 40 degrees from maximum capacity
>
>
>I have had no trouble getting 1 volt of RF using this procedure.  
>Currently I am having a problem with mine, getting all kinds of spurs 
>when I try to zero beat the receiver frequency.  It's going on the bench 
>next week to see what's going on.
>
>David
>KW4DH
>
>On 9/17/2011 2:31 PM, ewirtz wrote:
>> Hi,
>>
>> I'm working on a sick Invader 200. First of all I need to find a good
>> T2, the 9MHz Amplifier Tuning transformer, or a suitable replacement.
>> Second if any of you guys know where I can find typical RF voltage
>> measurement data for the 9 MHz amp, 1st mixer etc. I'm sure someone out
>> there has suffered through the same things I am with this worth brute.
>> Any help or advice will be gratefully appreciated. Please don't tell me
>> to trash it instead. Hi!!
>>
>> 73,
>>
>> Ed, K?BKA
>>
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>
>-- 
>"There are two means of refuge from the miseries of life.  Music and cats." ~ Albert Schweitzer ~
>
>
>
>------------------------------
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>End of Johnson Digest, Vol 92, Issue 10
>***************************************