Thanks Maurizio: In order to evaluate this we have to know
a) what kind of amplifier it was?
b) in what condition were the tubes?
c) did the operators have the knowledge how to properly tune-up and
maybe did it too long
which easily makes those tubes going soft - soft tubes splatter very
often
d) were the tubes matched?
e) maybe those italian guys who used those amplifiers had their
microphone gain way up as we
often have heard in the past on 27 MHz?
As I reported some time ago EIMAC reported in one of their Application Notes
a 4CX300 in a super cathode configuration ( grid tied to cathode and
grounded screen grid ) that was v e r y linear (46 db 3rd order and 49 db
5th order - they did not say if it was relative to pep or one of the tones?
) and had a very low no signal plate current (15 mA ). Output was 375 watts
for 75 watts, driving power. If we use those, say 3 or 4, PL509s or 8072s
in the same way, we may ( and I do not know yet ) get the 6-8 dbs I want.
The tubes will not get so hot too which enables me to use compact muffin
fans, who knows? The PL 509 DAF I mentioned should really be tested by
someone also.
What about the RAKE linear Mauritzio? Nice to have you on board on this
reflector.
Hej daa de Hans
----------
>Från: "Maurizio Panicara" <i4jmy@iol.it>
>Till: "Lars Harlin" <harlins@swipnet.se>, "sm5ki" <sm5ki@algonet.se>,
"measures" <measures@vcnet.com>, "AMPS" <amps@contesting.com>
>Ämne: R: [AMPS] Discussions... 3/2 Power law
>Datum: sön 2 jan 2000 00.08
>
>
>There was an italian company producing and selling an HF amplifier like
>that, using that tubes.
>The amplifier was derived from a CB one produced by the same company and was
>a total failure.
>The area of application where sweep tubes had always a big success, likewise
>splatters and very distorted signals, is not the same were transmitting
>tubes must be used.
>
>73,
>Mauri I4JMY
>
>
>-----Messaggio Originale-----
>Da: Lars Harlin <harlins@swipnet.se>
>A: sm5ki <sm5ki@algonet.se>; measures <measures@vcnet.com>; AMPS
><amps@contesting.com>
>Data invio: sabato 1 gennaio 2000 19.41
>Oggetto: SV: [AMPS] Discussions... 3/2 Power law
>
>
>>
>> SM5KI:
>> >No heavy and big squirrel-cage fan needed. Light weight simple
>> > voltage doubler circuits instead of a heavy anode transformer. Using PL
>> > 509/519s TV sweep tubes instead with filaments in series from the mains,
>I
>> > could get rid of the relative heavy filament transformer as well. This
>could
>> > give some 6 - 8 db increase from the transceivers 100 W which is enough
>for
>> > the purpose. It works - PA0FRI described a DAF with four PL 519s in the
>> > 8/1992 issue of RSGBs RadCom page162 - he says it shows well in a
>two-tone
>> > test and on -the -air tests were encouraging. PL 509 = 40KG6A.
>>
>> Hans,
>>
>> I really like this idea! Let me know how it works out. One caution only,
>be very careful with
>> saftey! A bit nasty if the chassis is at the same potential as the 240 V
>mains phase lead....huh...
>>
>> 73 de Lars
>
>
>
>
>
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