[ARC5] Modifying 1625s

Wed Jan 11 14:48:03 EST 2012

   Well, you know we are sometimes too picky.
I heard a ham complaining about his boss, who was from India.
He was saying how stupid he was because he was saying that his telephone 
wire had a shortage instead of
short.  Well, I thought about it and then understood the real problem. The 
both were technically wrong.
The telephone did not have a short. And if it did short what? It is a short 
circuit.
It is not either one, a short or shortage.
73
Bill wa4lav

At 12:48 PM 1/11/2012 -0500, mac wrote:
>"Confining" is a more descriptive term for the electrical function the 
>plates perform, read the article.  The King's or anybody else's English 
>has nothing to do with it.
>
>Dennis D. w7qho
>Glendale, CA
>
>*****************
>
>On Jan 11, 2012, at 4:45 AM, Fuqua, Bill L wrote:
>
>>We Americans must appologize for our poor English. These devices are 
>>Vacuum Valves and come in boxes of various colours.
>>
>>________________________________________
>>From: <mailto:arc5-bounces at mailman.qth.net>arc5-bounces at mailman.qth.net 
>>[<mailto:arc5-bounces at mailman.qth.net>arc5-bounces at mailman.qth.net] On 
>>Behalf Of Dennis DuVall [<mailto:scr522 at earthlink.net>scr522 at earthlink.net]
>>Sent: Wednesday, January 11, 2012 2:23 AM
>>To: ARC-5 List
>>Subject: Re: [ARC5] Modifying 1625s
>>
>>All,
>>
>>More accurately beam "confining" plates.  This subject comes up about
>>once a year.  For more than you ever wanted to know about beam
>>tetrodes see 
>><<http://www.r-type.org/static/btet.htm>http://www.r-type.org/static/btet.htm>
>>
>>Dennis D.  W7QHO
>>Glendale, CA
>>
>>******************
>>On Jan 10, 2012, at 10:41 PM, Dennis Monticelli wrote:
>>
>>>I can only add to the discussion that RCA tubes cannot be modified.
>>>Their beam forming plates are tied internal to the envelope.
>>>
>>>Dennis AE6C
>>>
>>>On 1/10/12, Glen Zook <<mailto:gzook at yahoo.com>gzook at yahoo.com> wrote:
>>>>The secret to modifying 1625 tubes to be used in grounded-grid is
>>>>to get the
>>>>"right" brands.  Some brands have the beam forming plates connected
>>>>inside
>>>>the glass envelope and some brands have the beam forming plates
>>>>connected
>>>>outside of the glass envelope.  The latter can be modified and the
>>>>former
>>>>cannot be modified.
>>>>
>>>>Glen, K9STH
>>>>
>>>>
>>>>Website:  <http://k9sth.com>http://k9sth.com
>>>>
>>>>
>>>>________________________________
>>>>From: Kenneth G. Gordon 
>>>><<mailto:kgordon2006 at frontier.com>kgordon2006 at frontier.com>
>>>>To: <mailto:ARC5 at mailman.qth.net>ARC5 at mailman.qth.net
>>>>Sent: Tuesday, January 10, 2012 11:49 AM
>>>>Subject: Re: [ARC5] Modifying 1625s
>>>>
>>>>On 10 Jan 2012 at 1:31, 
>>>><mailto:hwhall at compuserve.com>hwhall at compuserve.com wrote:
>>>>
>>>>>>Just curious. How do you modify a 1625 ??
>>>>>
>>>>>Certain brands had the beam forming grids brought out of the glass &
>>>>>connected to the cathode inside the phenolic octal base. You could
>>>>>remove the base or cut a hole in it and rewire the beam forming grid
>>>>>to a separate pin, for three independent grids. I think the standard
>>>>>practice then was to ground all the grids & run the tubes as
>>>>>grounded
>>>>>grid amplifiers that typically needed no neutralization.
>>>>
>>>>Yes. Exactly. In fact, that entire procedure and the amp that
>>>>resulted was the subject of an article in at least one ARRL Handbook
>>>>of the period. Used 4 ea "modified" 1625s in GG and the ARC-5 roller
>>>>inductor in the front. It was a nice-looking little amp and,
>>>>apparently, worked quite well.
>>>>
>>>>As I remember it, it was good for about 300 watts input.
>>>>
>>>>Since, at the time, many of the hams who were experimenting with SSB
>>>>were using such exciters as the CE-10 and CE-20 with 10 and 20 watts
>>>>output respectively, this provided a significant improvement in power
>>>>at relatively low cost.
>>>>
>>>>I have a CE-20A and the factory "458" VFO which was built on an ARC-5
>>>>transmitter, the BC-458.
>>>>
>>>>The combo is a nice little phasing rig with a lot of good features.
>>>>
>>>>Ken W7EKB
>>>>______________________________________________________________
>>>>ARC5 mailing list
>>>>Home: 
>>>><http://mailman.qth.net/mailman/listinfo/arc5>http://mailman.qth.net/mailman/listinfo/arc5
>>>>Help: <http://mailman.qth.net/mmfaq.htm>http://mailman.qth.net/mmfaq.htm
>>>>Post: <mailto:ARC5 at mailman.qth.net>mailto:ARC5 at mailman.qth.net
>>>>
>>>>This list hosted by: <http://www.qsl.net>http://www.qsl.net
>>>>Please help support this email list: 
>>>><http://www.qsl.net/donate.html>http://www.qsl.net/donate.html
>>>>______________________________________________________________
>>>>ARC5 mailing list
>>>>Home: 
>>>><http://mailman.qth.net/mailman/listinfo/arc5>http://mailman.qth.net/mailman/listinfo/arc5
>>>>Help: <http://mailman.qth.net/mmfaq.htm>http://mailman.qth.net/mmfaq.htm
>>>>Post: <mailto:ARC5 at mailman.qth.net>mailto:ARC5 at mailman.qth.net
>>>>
>>>>This list hosted by: <http://www.qsl.net>http://www.qsl.net
>>>>Please help support this email list: 
>>>><http://www.qsl.net/donate.html>http://www.qsl.net/donate.html
>>>______________________________________________________________
>>>ARC5 mailing list
>>>Home: 
>>><http://mailman.qth.net/mailman/listinfo/arc5>http://mailman.qth.net/mailman/listinfo/arc5
>>>Help: <http://mailman.qth.net/mmfaq.htm>http://mailman.qth.net/mmfaq.htm
>>>Post: <mailto:ARC5 at mailman.qth.net>mailto:ARC5 at mailman.qth.net
>>>
>>>This list hosted by: <http://www.qsl.net>http://www.qsl.net
>>>Please help support this email list: 
>>><http://www.qsl.net/donate.html>http://www.qsl.net/donate.html
>>
>>______________________________________________________________
>>ARC5 mailing list
>>Home: 
>><http://mailman.qth.net/mailman/listinfo/arc5>http://mailman.qth.net/mailman/listinfo/arc5
>>Help: <http://mailman.qth.net/mmfaq.htm>http://mailman.qth.net/mmfaq.htm
>>Post: <mailto:ARC5 at mailman.qth.net>mailto:ARC5 at mailman.qth.net
>>
>>This list hosted by: <http://www.qsl.net>http://www.qsl.net
>>Please help support this email list: 
>><http://www.qsl.net/donate.html>http://www.qsl.net/donate.html
>>______________________________________________________________
>>ARC5 mailing list
>>Home: 
>><http://mailman.qth.net/mailman/listinfo/arc5>http://mailman.qth.net/mailman/listinfo/arc5
>>Help: <http://mailman.qth.net/mmfaq.htm>http://mailman.qth.net/mmfaq.htm
>>Post: <mailto:ARC5 at mailman.qth.net>mailto:ARC5 at mailman.qth.net
>>
>>This list hosted by: <http://www.qsl.net>http://www.qsl.net
>>Please help support this email list: 
>><http://www.qsl.net/donate.html>http://www.qsl.net/donate.html