>Hi Rich!
>
>I just picked up this MLA-2500B from E-Bay.
>It's nice, but the door knob padders had been
>"robbed."
>For 160 meters, you need around 300 pf of padding
>on C1 to go with the 19 uh inductance. The 150 pf
>sounds good for 80 meters. (8 uh on the coil)
>Now for the loading part...this is critical, because the
>Load variable cap is only 500 pf. Not a very large
>"tuning window" on 160. I figure around 2000 pf for
>the padders here. About half that for 80m, and 180 pf
>works fine on 40m...I want to be sure on all of these
>so I can get it right the first time!
>
>Apparently, the 2500B had several changes in the tank.
Amen.
>The book that came with this 2500B is not anywhere
>close to what needs to be there. Someone had removed
>all the door knob caps, and apparently was using the
>amp as a "single-bander" on 80m.
The orig. padder caps were reportedly bypass-type caps. The Alpha 77SX
made the same mistake.
>
later, Phil, K5PC
>
>
>Phil Clements
>410 VZ CR 4903
>Ben Wheeler, TX 75754
>
>----- Original Message -----
>From: "measures" <2@vc.net>
>To: "Phil Clements" <philk5pc@tyler.net>; "AMPS" <amps@contesting.com>
>Sent: Thursday, July 27, 2000 11:20 AM
>Subject: Re: [AMPS] MLA-2500B Question
>
>
>>
>> >I need the values of the padder door knob
>> >caps on the MLA-2500B Dentron amp. The
>> >2500 and 2500B were apparently different.
>> >Thanks,
>> >Phil, K5PC
>> >
>> In a discussion with an MLA owner this week, the padder values are
>> apparently wrong. To make a padder that works, parallel , 50pF and100pF,
>> 5kV doorknobs. The Tune-C should not be fully meshed or fully unmeshed
>> at the band edges.
>>
>> - Rich..., 805.386.3734, www.vcnet.com/measures.
>> end
>>
>>
>> --
>> FAQ on WWW: http://www.contesting.com/FAQ/amps
>> Submissions: amps@contesting.com
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>>
>>
>
>
>
- Rich..., 805.386.3734, www.vcnet.com/measures.
end
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