>
>--- rlm <2@vc.net> wrote:
>> >
>> >My question is what is the weak link that prevents operating CW at
>> the
>> >higher voltage and is there a mod to get around this?
>>
>> The mod: A higher-speed temp-controlled DC-brushless cooling fan and
>> a
>> Peter Dahl Hipersil? HV transformer. The difference at the Rx-end
>> would
>> be about a quarter of one S-unit.
>> >
>
>Since I run a '922, I have a question: The "quarter S-unit" isn't my
>concern. But would the added cooling + heavy duty XFMR provide added
>headroom?
** for RTTY contesting, yes.
>In other words, I know it won't affect the signal strength
>much, but would it be cleaner since it could handle higher peaks
>instead of flat-topping & splattering (given the same drive level)?
** Operating the tubes within their linear region makes for good
linearity. 3-500Z/8002 IMD is over 42db down, which is better than
virtually all radios.
>Also, which Peter Dahl XFMR would work? I looked at their website and
>found nothing for the '922.
** It would be a custom unit. The original xfmr is fairly ok, which
could be why Peter Dahl does not offer a 922 HV xfmr. Even though the
Tune-C has a BD potential of 6kV, and the filter C is rated at 4000WV, a
4000VDC supply would seem to be do-able, however, the 922's bandswitch is
most likely not up to a 4000VDC supply.
>
cheerz, Joe
- R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
www.vcnet.com/measures.
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