[Boatanchors] Hammarlund HQ-170A vs. National NC-300

[kim.herron at sbcglobal.net]

Hi Pete!!

    We both know that Lafayette bought tubes from major manufacturers.
----- Original Message ----- 
From: "Peter Markavage" <manualman at juno.com>
To: <boatanchors at mailman.qth.net>
Sent: Tuesday, July 15, 2008 10:56 PM
Subject: Re: [Boatanchors] Hammarlund HQ-170A vs. National NC-300


>I use only Lafayette tubes in my radios.
>
> Pete, wa2cwa
>
> On Tue, 15 Jul 2008 22:13:50 -0400 <kim.herron at sbcglobal.net> writes:
>> Hi Carl,
>>     Yes, you do need to pay attention to the 6C4 tube.  It is a
>> problem
>> if that tube doesn't perform.  It needs to be a Sylvania, GE or RCA.
>>  If
>> you do that, you're in like Flynn.  Second tier supplier tubes DO
>> NOT
>> WORK, PERIOD!!!.  Can you say drifty???
>>
>> Kim  W8ZV
>> ----- Original Message ----- 
>> From: "Carl" <km1h at jeremy.mv.com>
>> To: "Bob Young" <youngbob53 at msn.com>; <boatanchors at mailman.qth.net>
>> Sent: Tuesday, July 15, 2008 6:26 PM
>> Subject: Re: [Boatanchors] Hammarlund HQ-170A vs. National NC-300
>>
>>
>> > Over on another forum many of the later HQ owners complain about
>> > having to select a 6C4 that either doesnt continuously drift or
>> quit
>> > working at the lower end of the top end band. Then the life is
>> rather
>> > short.
>> > Sounds like a design problem across many models.
>> >
>> > National made several changes in the NC-300 and there was also a
>> > factory alignment glitch in the early ones. With the second
>> conversion
>> > oscillator switch to xtal control (every 300 that came in for
>> service
>> > had that done automatically) drift was almost nil after a short
>> > warmup.
>> >
>> > I used the 300 primarily as an IF for 50 thru 1296 converters in
>> the
>> > early to mid 60's when AM was still more popular than SSB on those
>>
>> > bands. I believe I paid $100 for it and the speaker.
>> >
>> > My own TX gear was AM/SSB and CW and mostly homebrew with a
>> converted
>> > NCL-2000 on 6 (which I still use) and a pair of  4CX250B's on 144,
>> 220
>> > and 432 with a common PS and PP 811A's modulator. The NCL ran as
>> an AM
>> > linear at ~ 400W out and the other amps were switchable from Class
>> C
>> > to AB2.
>> >
>> > The NC-300 lasted for about 3 years and was replaced by a 75A4
>> with a
>> > Collins NB when SSB really caught on and QRM was often intense. I
>> used
>> > 10M for the IF and not Nationals converter band.
>>
>> > Those were fun days.
>> >
>> > Carl
>> > KM1H
> _______________________________________________