TenTec sent me a mod sheet. Its just a resistor swap for one mod. The
SWR mod requires removal of a PCB board and cutting a trace, so you can
add a new ground wire. What they do NOT mention in my mod sheet is
that you should only solder the grounded end of the new wire when you
have located the point of minimum SWR ... They gave me that hint at
Dayton a couple of years back. I freed the wire and used an alligator
clip to temporarily attach it to the ground trace. Then I moved it along
until I hit the null point on the SWR meter (with the rig on 28 mHz).
Its quite easy to do with the board in place, because its on the upper
exposed edge. Then I soldered it down again.
Swapping the memory requires at least partial removal of the front
panel. Make sure you have the right Allen key before you start. The
antenna switch coupling is unusual.
Hope this helps. If you get stuck I'll copy the mod sheet to you.
John
P.S. My 253 will load a coax fed 40m diamond shape quad loop on 160m as
well as on 80. To prove it I have a QSL card from D2CW. The 40m dipole
is too short, but I'd expect an 80m dipole to load up.
On 13-Apr-00 Jan Ditzian wrote:
>
> John - G3JAG wrote:
>
>> Hi Dan
>>
>> I use a 253
>
>
>
>> Known snags/mods. There are two official mods which I know about.
>> One
>> reduces the power needed to tune (30-50 watts). The other corrects
>> an
>> SWR metering error. The non-volatile RAM chip used to store data has
>> a
>> finite life and dies on you after very extended service.
>> Replacements
>> were expensive here in UK, but I got three spares last week for
>> around
>> $2 each. The trade outlet told me they have over 200 in stock. Looks
>> like this chip should not be a problem to get and in any case TT can
>> probably help.
>
> John,
>
> Where can I find information on the mods?
>
> 73,
> Jan, KX2A
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