Most CB'ers would laugh at only one 8877
-----Original Message-----
> And then RF speech processors came along in that year such as the
Comdel.
> I
> still have mine!
I think I still have one of the Drake plug in "compressors".
>
> Now they have amps advertised regularly that will do 2200-2500W out
and no
> one cares any longer. How many out there drop the drive to their 8877
amp
> to 60-65W in order to be legal?
An amp with ONLY one 8877? <:-))
73
Roger (K8RI)
>
> Carl
> KM1H
>
>
> ----- Original Message -----
> From: "Roger" <sub1@rogerhalstead.com>
> To: <amps@contesting.com>
> Sent: Monday, July 23, 2007 3:59 PM
> Subject: Re: [Amps] Drake amplifier
>
>
>>
>>
>>
>>> 1KW input on CW, 2KW PEP on SSB was the FCC reg back then. For that
>>> reason
>>
>> Maybe a slight technicality, but the power limit was "1 KW AVERAGE dc
>> input
>> measured using a current meter with a 1/4 aecond time constant. There
was
>> only one limit, not seperate ones for CW and SSB. In grounded grid
you
>> were
>> supposed to add the exciter input to the amp input when figuring the
>> legal
>> limit.
>>
>> PEP varied widely on input and output due to voice characteristcs.
On
>> the
>> two "legal limit" amps I ran back then I consistently ran 2 KW PEP
>> "output"
>>
>>> many amps of that era had a CW/SSB plate voltage switch. Many left
it in
>>> the
>>> SSB position irregardless of the mode (; No sense in throwing away
3dB
>>> in
>>> a
>>> pileup.
>>>
>>
>> The CW position was also a tune-up position that allowed tuning for
tilt,
>> then switching to SSB with a higher plate voltage and not having to
>> retune.
>> Actually many of the amps used voltage doublers and if you tuned up
in
>> the
>> SSB position it'd drag the voltage down to the point they'd be
mistuned
>> running SSB. My old Alpha 76A has a heavy enough power supply but the
>> manual
>> still has you tune in the CW position to prevent over heating the
tubes.
>>
>> 73
>>
>> Roger (K8RI)
>>> Carl
>>> KM1H
>>>
>>>
>>> ----- Original Message -----
>>> From: <Gudguyham@aol.com>
>>> To: <garyschafer@comcast.net>; <amps@contesting.com>
>>> Sent: Monday, July 23, 2007 12:33 PM
>>> Subject: Re: [Amps] Drake amplifier
>>>
>>>
>>>>
>>>> In a message dated 7/23/2007 12:21:44 P.M. Eastern Daylight Time,
>>>> garyschafer@comcast.net writes:
>>>>
>>>> I have a drake L7 amp.
>>>> How much power out do you typically get from a drake L4 or L7 amp?
I
>>>> have
>>>> 95
>>>> watts drive and get just short of 1100 watts on 40 meters.
>>>>
>>>> The amp's wattmeter and a bird wattmeter with a brand new slug
agree
>>>> almost
>>>> exactly.
>>>>
>>>> This seems a little low or is that about all that can be expected
from
>>>> the
>>>> 3-500Z's. They run at 2450 volts on the plates and 230 ma grid
>>>> current.
>>>>
>>>> Thanks
>>>> Gary K4FMX
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> Hi Gary, Yup, that is about right 110-1200 watts out with around
100
>>>> watts
>>>> of drive. If you have a look at an AL-82, it will do about 1600
watts
>>>> out
>>>> with 100 watts in. The difference is in the fact that the
Ameritron
>>>> AL-82
>>>> runs
>>>> the anode at about 3600-3700 volts. The extra plate voltage really
>>>> makes
>>>> the
>>>> 3-500Z's play great. The "HOT" set up for the Drake L4 or L7
would be
>>>> to
>>>> build up a better HV supply. The Drake tank circuit can take 4KV
no
>>>> problem.
>>>> But what you are seeing now is right on the money. You have to
>>>> remember
>>>> that
>>>> when the L4/L7 were made, the maximum power permissible by the FCC
was
>>>> ONE
>>>> KILOWATT DC INPUT. That being so, the amp companies did not run a
>>>> pair
>>>> of
>>>> 3-500's to their full potential so they got by with wimpy power
>>>> supplies.
>>>> Put a
>>>> good power supply on an L4 and it will perform nicely. Easy legal
>>>> limit
>>>> amp
>>>> plus. Oddly, the Drake RF deck makes a great conversion to an
8877
>>>> and
>>>> handles the 2KW easily.
>>>> 73 Lou
>>>>
>>>>
>>>>
>>>> ************************************** Get a sneak peek of the
all-new
>>>> AOL
>>>> at
>>>> http://discover.aol.com/memed/aolcom30tour
>>>> _______________________________________________
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>>>>
>>>
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>>
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