jeremy-ca wrote:
>
> Huh? What is that supposed to mean? They either have the 3CX800 or the
> CPX installed (or a Y version). Im not aware of any commercial ham amp
> that is pulse rated.
>
IIRC for a while Henry listed a either a 2002A or 3002A as a legal limit
amp. I think it was on 6-meters and ran a 3CPX800. It wasn't rated for
pulse, but it did have take advantage of the extra cathode emission
available.
Roger (K8RI)
> Carl
> KM1H
>
>
>
>>
>>
>> 73
>>
>> Roger (K8RI)
>>>
>>> They must provide extreme levels of linearity in medical service and
>>> are conservatively operated. In amateur service they are known for
>>> ruggedness and superb linearity.
>>>
>>> Bandwidth has nothing to do with it.
>>>
>>> Carl
>>> KM1H
>>>
>>>
>>>
>>> ----- Original Message ----- From: "Bill Fuqua" <wlfuqu00@uky.edu>
>>> To: "jeremy-ca" <km1h@jeremy.mv.com>; "Roger (K8RI)"
>>> <sub1@rogerhalstead.com>
>>> Cc: "Amps" <amps@contesting.com>
>>> Sent: Monday, March 24, 2008 11:59 AM
>>> Subject: Re: [Amps] What is this amp set up for
>>>
>>>
>>>> I have gotten several 200 MHz power pulsed amplifiers from
>>>> University surplus sales.
>>>> These were used in MRI systems. One interesting one had a version
>>>> of the 8877 with out
>>>> fins clamped in a 1/4 wave cavity. It had a solid state driver
>>>> amplifier that was also pulse rated.
>>>> I think a hint may be the spec. of 200 MHz plus or minus a few MHz
>>>> and a 2kW pulse rating for
>>>> power. Pulse operation is usually not used in amateur work due to
>>>> the wide band width.
>>>>
>>>> 73
>>>> Bill wa4lav
>>>>
>>>>
>>>> At 08:52 AM 3/23/2008 -0400, jeremy-ca wrote:
>>>>> With 2M amps being not that uncommon the price is usually lower.
>>>>>
>>>>> With the only 222 amps being custom made or modified as that one
>>>>> they tend
>>>>> to be more in demand. And you know what happens on Ebay when the
>>>>> frenzy
>>>>> starts.
>>>>>
>>>>> Those holes look to be for extra air flow thru the cover after it
>>>>> got hot
>>>>> and deformed. I'd open it all the way and install a silicon rubber
>>>>> chimney
>>>>> with a non restrictive mesh on top. I had to do that with my 144
>>>>> and 222
>>>>> amps; made a huge difference and no more tuning drift.
>>>>>
>>>>> Prices are even higher for a good 432 amp in the 8938 and 2x 3CX800
>>>>> category.
>>>>> I gave up finding a 8938 at a good price and wound up rebuilding a
>>>>> Collins
>>>>> USAF 350 MHz cavity amp with a GE 2500W dissipation monster
>>>>> tetrode. It was
>>>>> designed for a KW out as an AM linear.
>>>>>
>>>>> Carl
>>>>> KM1H
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> ----- Original Message -----
>>>>> From: "Roger (K8RI)" <sub1@rogerhalstead.com>
>>>>> To: "jeremy-ca" <km1h@jeremy.mv.com>
>>>>> Cc: "Amps" <amps@contesting.com>
>>>>> Sent: Sunday, March 23, 2008 2:18 AM
>>>>> Subject: Re: [Amps] What is this amp set up for
>>>>>
>>>>>
>>>>> > jeremy-ca wrote:
>>>>> >> When I first saw that listing it said modified; I see he has
>>>>> revised >> it.
>>>>> >>
>>>>> >> Thats not a bad price for smoke on 222 if the tube is perfect and
>>>>> >> trimming back the strip line should be rather easy
>>>>> > I would think it's too high even with a new tube. Really nice ones
>>>>> > unmodified on 2, or 6-meters have been going for around $1400
>>>>> (give or
>>>>> > take) Look carefully at the top. It is bent in and has a
>>>>> circular row > of
>>>>> > what appear to be holes. I have one on 2 that is *almost*
>>>>> mint. It
>>>>> > looked crappy when I purchased it at a swap. I figured I could
>>>>> use it > for
>>>>> > parts and hoped for a reasonably good tube. A little cleaner and
>>>>> it > looks
>>>>> > almost new with a good tube.
>>>>> >
>>>>> > 73
>>>>> >
>>>>> > Roger (K8RI)
>>>>> >>
>>>>> >> My own amp for 222 is a 8877 and I scaled down a 2M version and
>>>>> then >> used
>>>>> >> a VNA for final trimming. I built it in a partially built Henry
>>>>> 44-46 >> MHz
>>>>> >> box I picked up in a swap.
>>>>> >>
>>>>> >> Carl
>>>>> >> KM1H
>>>>> >>
>>>>> >>
>>>>> >> Carl
>>>>> >> KM1H
>>>>> >> ----- Original Message ----- From: "Roger (K8RI)"
>>>>> >> <sub1@rogerhalstead.com>
>>>>> >> To: "jeremy-ca" <km1h@jeremy.mv.com>
>>>>> >> Cc: "Amps" <amps@contesting.com>
>>>>> >> Sent: Saturday, March 22, 2008 9:19 PM
>>>>> >> Subject: Re: [Amps] What is this amp set up for
>>>>> >>
>>>>> >>
>>>>> >>> jeremy-ca wrote:
>>>>> >>>> Hmmm, his description says it is modified for 220.
>>>>> >>>
>>>>> >>> Isn't that "modifiable" to 220?
>>>>> >>> Although advertised as a 2-meter amp, "I'd guess" it's one of
>>>>> those >>> that
>>>>> >>> was used for plasma or industrial heating at 200 MHz that can be
>>>>> >>> modified for 220. Some outfit has had a similar one in very
>>>>> nice >>> shape
>>>>> >>> (with new tube)on there since last Fall with no takers. Their
>>>>> BIN >>> price
>>>>> >>> has finally started down. Unless they find some one who really
>>>>> wants
>>>>> >>> (and can use) one for 220 both are basically parts amps.
>>>>> >>>
>>>>> >>> I purchased one all set up for the 2-meter band in good shape
>>>>> that >>> only
>>>>> >>> required a good cleaning for less than he's asking for one
>>>>> that may
>>>>> >>> require a lot of work. I was learning about building filters
>>>>> for it >>> on
>>>>> >>> here last summer.
>>>>> >>>
>>>>> >>> 73
>>>>> >>>
>>>>> >>> Roger (K8RI)
>>>>> >>>> Carl
>>>>> >>>> KM1H
>>>>> >>>>
>>>>> >>>>
>>>>> >>>> ----- Original Message ----- From: "Roger (K8RI)"
>>>>> >>>> <sub1@rogerhalstead.com>
>>>>> >>>> To: "Amps" <amps@contesting.com>
>>>>> >>>> Sent: Saturday, March 22, 2008 7:59 PM
>>>>> >>>> Subject: [Amps] What is this amp set up for
>>>>> >>>>
>>>>> >>>>
>>>>> >>>>> the amp listed on
>>>>> >>>>>
>>>>> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=350038955687&ssPageName=ADME:X:AAQ:US:1123
>>>>>
>>>>>
>>>>> >>>>> is listed as a 2-meter amp but the specs list it as 200 MHz
>>>>> +/-10 >>>>> Mhz.
>>>>> >>>>> Also the output filter is far smaller than the one in my
>>>>> 2002A >>>>> which
>>>>> >>>>> is
>>>>> >>>>> set up for 2-meters.
>>>>> >>>>>
>>>>> >>>>> 73
>>>>> >>>>>
>>>>> >>>>> Roger (K8RI)
>>>>> >>>>> _______________________________________________
>>>>> >>>>> Amps mailing list
>>>>> >>>>> Amps@contesting.com
>>>>> >>>>> http://lists.contesting.com/mailman/listinfo/amps
>>>>> >>>>>
>>>>> >>>>
>>>>> >>>>
>>>>> >>>
>>>>> >>>
>>>>> >>
>>>>> >>
>>>>> >
>>>>> >
>>>>>
>>>>> _______________________________________________
>>>>> Amps mailing list
>>>>> Amps@contesting.com
>>>>> http://lists.contesting.com/mailman/listinfo/amps
>>>>
>>>>
>>>
>>>
>>
>>
>
>
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|