With my 238 tuner I too experienced issues with observed SWR drifting at
higher power values, but only under certain antenna configurations.
Conclusion, the 220pf capacitors wired parallel and associated with the Hi Z
and Lo Z switch were getting hot, thus changing values. I replaced each
pair with a Russian made 470 pf 2KV doorknob style capacitor. These can
be found on E-Bay for a nominal price.
Mounting was accomplished by drilling holes through the bottom plate in the
area of the original capacitors. It is a tight place to work but with a
little planning the result is a very nice professional job.
Problem solved.
73
Bob, K4TAX
----- Original Message -----
From: "David Cuttler" <davidcuttler@yahoo.com>
To: <tentec@contesting.com>
Sent: Monday, July 02, 2012 11:30 PM
Subject: Re: [TenTec] 229 swr circuit
>I own a 229 tuner, and I have never used the meter. If it ever died, I
>wouldn't care because it is of limited use. I would recommend finding a
>good external meter that will read CW & PEP like the Ameritron AWM-30 which
>is what I use, and forget about the 229 meter.
>
> Of more importance are the crummy disc capacitors in the tuning circuit.
> My tuner would not hold a setting, and the swr would drift all over when
> used on the lower bands until I replaced all of the the disc caps with
> Russian door knob caps that I purchased off Ebay. Now my 229 tuner is rock
> steady, and I have not had any issues with it after the modification.
>
> If your antenna does not need a tuner, then you will be happy with the 229
> as it is built, but if you are using antennas that are far from 50 ohms
> like my doublet that is fed with 450 ohm window line, the 229 in the
> factory configuration is a lousy piece of equipment.
>
> The meter is more bother than it is worth, unless you are like me, and
> need to have everything working correctly just because it's there!
>
> Sorry for the rant.
>
>
>
>
>
> _______________________________________________
> 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
|