It has been a while since I did the mod, but as I recall, I had to unsolder
the variable cap and coil to get closer to the solder tabs on the main
switch. I used long, thin needle-nose pliers to hook the tinned ends of the
wires to the switch tabs. It does take some manual dexterity to fit
everything in. It's a good idea to take some digital photos of the insides
before you start unsoldering anything so you can remember where everything
went.
Ron N6IE
www.N6IE.com
----- Original Message -----
From: "Jack Mandelman" <modeler@bellsouth.net>
To: <tentec@contesting.com>
Sent: Tuesday, March 04, 2008 6:55 AM
Subject: Re: [TenTec] 238 Tuner Mod
>I made a similar mod to my 229B tuner. However, instead of using
> doorknob caps I replaced the originals with 6KV 470pF Y5P ceramics.
> These capacitors are physically larger than the originals, having a
> thicker dielectric for increased breakdown voltage and larger plate
> surface area for increased current carrying capacity. The drift problem
> was nearly completely, but not entirely, mitigated. Complete
> disassembly of the tuner was unnecessary, since I was able to work in
> the tight space around the switch with small forceps.
>
> Now, I'm considering using the doorknob caps. Would appreciate any
> suggestions about disassembly of the tuner for easier installation of
> the doorknob caps.
>
> 73,
>
> Jack K1VT
>
>
>> I few months back, I modified my TT 238 tuner by changing out the disc
>> ceramic
>> caps with surplus Soviet military doorknob caps, which dramatically
>> improves
>> the power handling capability on 160 and 80 meters. Heating used to
>> cause the
>> SWR to 'drift', even at 100 Watts in some situations on 160. The mod
>> worked
>> well, and if anyone is interested, I have all the details and pictures
>> on my
>> website at www.n6ie.com.
>>
>> 73,
>> Ron N6IE
>> www.N6IE.com
>
> _______________________________________________
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> TenTec@contesting.com
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>
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