>
>Is the 500mA limit one imposed on safe conditions for the anode, or for the
>cathode?
>
// Neither. The 3-500Z has a linear peak-emission limit of c. 1.2a.
This corresponds to c. 400mA average. Initally, the 3-500Z had a rating
of 350mA. This was later increased
to 400mA.
>The question is based on SOA regarding Pdiss; I run my AL80B at all sorts of
>(intermittant) high current levels but without exceeding 500W dissipation,
>seems to take it very much in stride for the past 10 months of
>operation...no apparent change in anything:
>
// On CW or FM, this will probably fly ok. On SSB, driving a 3-500Z
above 400mA could result in a surprise tar and feathering at a hamvention
or flea market.
>600mA @ 2600V = 1560Wdc input; output (measured) = 1100W; apparent
>efficiency 70%, apparent Pd = 460W (realizing some drive power appears in
>the output). Under these condx the amp is just hitting a small amount of
>compression (<1 dB) but with more drive the output will continue to climb;
>problem is Ig, which gets hard to keep below 150mA when you drive it too
>hard.
// The grid diss is rated at 20w, 150mA x 85V is way under 20w.
>
>What, exactly, is the issue? Does Eimac even still manufacture a 3-500Z?
>
>WB2WIK/6
>
>"Each success only buys an admission ticket to a more difficult problem." --
>Henry Kissinger
>
>> -----Original Message-----
>> From: Vic Rosenthal [SMTP:rakefet@rakefet.com]
>> Sent: Friday, September 28, 2001 9:56 AM
>> To: AMPS
>> Subject: Re: [AMPS] Noises in electrolytic capacitors
>>
>>
>> 2 (Rich) wrote:
>>
>> > // (ref SB-1000 and AL-80 owners' manuals)
>> > When challenged on his assertion that the 3-500Z was re-rated by Eimac
>> > for 500mA
>>
>> I don't know why this keeps coming up, but the SB-1000 and AL80B manuals
>> talk
>> about running the plate current up to 500 ma for a short period during
>> tuning
>> only, so that you can tune the tank for the peak conditions that will
>> occur
>> during SSB use. They specifically say that you should reduce drive in CW
>> to
>> give you 400 ma., and make reasonabale statements about the meter swing
>> you
>> should expect on SSB.
>>
>> 73,
>> Vic, K2VCO
>> Fresno CA
>>
>> --
>> FAQ on WWW: http://www.contesting.com/FAQ/amps
>> Submissions: amps@contesting.com
>> Administrative requests: amps-REQUEST@contesting.com
>> Problems: owner-amps@contesting.com
>
>--
>FAQ on WWW: http://www.contesting.com/FAQ/amps
>Submissions: amps@contesting.com
>Administrative requests: amps-REQUEST@contesting.com
>Problems: owner-amps@contesting.com
>
>
- R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures.
end
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