Re: Commander HF-2500
Hi Alek, I’ve seen some of the older units and worked on them. ?The real old ones had no grid trip circuit and so I made up a circuit board ?with a trip circuit and implement it on the old units.
By
Louis Parascondola
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#40976
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Re: Drake L-7
Hello,
** No, I don't have the service manual for this amp. If you could share it with me, it would be appreciated.
** Your capacitor 'A' went with your old RF choke.
A= 47 pF
B= 307
By
Fran?ois
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#40975
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Re: Drake L-7
Fran?ois, here are the exact capacitors I used to replace C41 and C42 in my L7:
https://www.rfparts.com/catalogsearch/result/?q=580050-7P
https://www.rfparts.com/catalogsearch/result/?q=580300-7
By
Fran?ois
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#40974
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Re: Drake L-7
Fran?ois, here are the exact capacitors I used to replace C41 and C42 in my L7:
https://www.rfparts.com/catalogsearch/result/?q=580050-7P
https://www.rfparts.com/catalogsearch/result/?q=580300-7
I
By
Paul K6PO
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#40973
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Commander HF-2500
This is a real long shot.
I have an old Commander HF-2500 which I love very much. It is Serial Number 186 and it conforms with the printed manual and schematic of June 1990.
However, there is no
By
Alek Petkovic
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#40972
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Re: Drake L-7
Hi Francois,
I did not document my changes and sold the amp a few years ago.
I remember the green capacitor (B) but not (A). That could easily be a memory leakage on my side but I couldn’t
By
Evert Bakker
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#40971
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Re: Drake L-7
Hello
I am weak in technology (I am 75 years old). It seems to me that you are pointing out the two curious plate capacitors A = C41 (47 pF) and B = C42 (307 pF).
Could you give me,
By
Fran?ois
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#40970
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Re: Drake L-7
The reason is in this message
/g/ham-amplifiers/message/40898
--
F1AMM
Fran?ois
De la part de Evert Bakker via groups.io
Envoyé : samedi 25 janvier 2025 19:38
By
Fran?ois
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#40969
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Re: Drake L-7
I recently bought this L 7 (about $1000) from an OM who used it very little. It has the serial number 672.
On this device, the air is sucked from the bottom of the case by a kind of scoop. It is a
By
Fran?ois
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#40968
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Re: Drake L-7
Why do you want to see these tubes all the time?
It is the most reliable amp I’ve had.
You can push this amp to all its limits and beyond, it just won’t die.
Even when it starts to stink
By
Evert Bakker
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#40967
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Re: Drake L-7
It seems your lid or top sheet metal has been changed. Mine has holes and I can see the tubes.
By
mike repinski
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#40966
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Re: Drake L-7
The top sheet metal is a solid sheet metal. You can see, very badly, through the fan.
Removing the top panel: ok. To do a short test, it is a solution but in operation it is not reasonable, if
By
Fran?ois
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#40965
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Re: Drake L-7
Take the top-cover off and use something to push the rod down so the HV will pass through.
As long as you know what you are doing … (I shorted that switch)
BUT TAKE CARE.
There is no room for
By
Evert Bakker
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#40964
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Re: Drake L-7
You should be able to see them thru the top of the amp turning red.
By
mike repinski
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#40963
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Drake L-7
Hello
I am in the process of putting a Drake L 7 amplifier back into operation.
I was advised on this forum to bring the anodes of the 3-500Z to red to maintain the quality of the vacuum.
By
Fran?ois
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#40962
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Re: Two tones test generator
In the same way that there are synthetic white noise generators, from a pseudo-random code, are there synthetic pink noise generators?
This pink noise modulating in SSB seems to me to be a very
By
Fran?ois
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#40961
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Re: Two tones test generator
Excellent idea...... and I had forgotten all? about it.? ?My Behringer DEQ-2496? ( 24 bit - 96 khz)? mastering processor has a pink noise generator in it.? ?I checked my old notes, and when fed
By
Jim VE7RF
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#40960
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Re: AL-82 Date of Manufacture
I have a 2014 AL-82 and two of the components inside have manufacture dates
on them. One was the power supply and I don't remember the other might have
been the blower.
[email protected]>
By
Matt KA6JAR
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#40959
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AL-82 Date of Manufacture
Hello,
Can the vintage or date of manufacture be determined from the serial number on an Ameritron AL-82?
Thanks and 73,
Garry - K4OR
By
Garry - K4OR
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#40958
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?Southeastern VHF Society 2025 Conference Announcement & Call For Papers
#2MAmplifier
?
Southeastern VHF Society 2025 Conference Announcement & Call For Papers
Quality Inn , 3095 Wilma Rudolph Blvd, Clarksville, TN 37040
April 4th and 5th, 2025
Papers and presentations are
By
Robin Midgett
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#40957
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