[Boatanchors] Multi-Elmac AF-68 and AF-68A

[Charles Vest]

Do you have a link to the battery you are using from e-bay ?

Thank you ,
Charlie , W5COV

> On February 21, 2019 at 11:55 AM aerosmithl <aerosmithl at comcast.net mailto:aerosmithl at comcast.net > wrote:
> 
> 
>     You can purchase all the 22 1/2 volt batteries from China with fast shipping. Check E-bay. I bought two for my Elmacs.
> 
>     Sent from my iPad
> 
>         > > On Feb 21, 2019, at 11:41 AM, D C _Mac_ Macdonald <k2gkk at hotmail.com mailto:k2gkk at hotmail.com > wrote:
> > 
> >         Hi, Gary.
> > 
> >         I could not find anything through Google about the differences. However, the originals had two known problems: 1) Modulator driver transformer quickly went bad, frequently replaced. 2) Negative 22.5 Volt Bias for 6L6 modulator tubes derived from a 22.5 Volt battery with short life (try finding one today). Build voltage doubler from 12.6 VAC filament supply and then hand-select Zener diode(s) to get to 22.5 Volts.
> > 
> >         The "A" model MAY have fixed one or both of those problems.
> > 
> > 
> >         73 de Mac, K2GKK/5
> >         Since 30 Nov 1953
> >         Oklahoma City, OK
> >         USAF, Retired ('61-'81)
> >         FAA, Retired ('94-'10)
> > 
> >         ________________________________
> >         From: boatanchors-bounces at mailman.qth.net mailto:boatanchors-bounces at mailman.qth.net <boatanchors-bounces at mailman.qth.net mailto:boatanchors-bounces at mailman.qth.net > on behalf of Gary H. Harmon, Jr. <gharmon at idworld.net mailto:gharmon at idworld.net >
> >         Sent: Thursday, February 21, 2019 09:46
> >         To: 'BOATANCHORS2 LIST'
> >         Subject: [Boatanchors] Multi-Elmac AF-68 and AF-68A
> > 
> >         Looking for a schematic or manual for a AF-68A in order to determine the
> >         differences in the two.
> > 
> > 
> > 
> >         Thanks in advance.
> > 
> > 
> > 
> >         Gary H. Harmon, Jr. - K5JWK - HAM Radio and ATARI Archaeologist
> > 
> >         6003 Archwood
> > 
> >         San Antonio, TX 78239-1504
> > 
> >         (210) 657-1549 <home>
> > 
> >         (210) 884-6926 <cell and text>
> > 
> >         (210) 657-1549 <FAX with prior notification>
> > 
> >         gharmon at idworld.net mailto:gharmon at idworld.net
> > 
> > 
> > 
> >         "Retirement = Every day is a Saturday except Sunday"
> > 
> >         "Real radios glow in the dark"
> > 
> >         "Too many projects, not enough time"
> > 
> > 
> > 
> >         https://eur04.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.grissomroadcoc.org&data=02%7C01%7C%7Cf393b397c91f48af153e08d69813be04%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C636863607887130052&sdata=N0EqIM3sEfOdEgl4mBy3%2FpV0SbqyqbvrTngWwUkW85M%3D&reserved=0 https://eur04.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.grissomroadcoc.org&data=02%7C01%7C%7Cf393b397c91f48af153e08d69813be04%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C636863607887130052&sdata=N0EqIM3sEfOdEgl4mBy3%2FpV0SbqyqbvrTngWwUkW85M%3D&reserved=0
> > 
> > 
> > 
> >         ______________________________________________________________
> >         Boatanchors mailing list
> >         Home: https://eur04.safelinks.protection.outlook.com/?url=http%3A%2F%2Fmailman.qth.net%2Fmailman%2Flistinfo%2Fboatanchors&data=02%7C01%7C%7Cf393b397c91f48af153e08d69813be04%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C636863607887130052&sdata=vW5%2FuPDY%2BsR7BdO4fzXIJ3%2BA2ozs%2FV5WH%2FEdUsrrhb4%3D&reserved=0 https://eur04.safelinks.protection.outlook.com/?url=http%3A%2F%2Fmailman.qth.net%2Fmailman%2Flistinfo%2Fboatanchors&data=02%7C01%7C%7Cf393b397c91f48af153e08d69813be04%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C636863607887130052&sdata=vW5%2FuPDY%2BsR7BdO4fzXIJ3%2BA2ozs%2FV5WH%2FEdUsrrhb4%3D&reserved=0
> >         Help: https://eur04.safelinks.protection.outlook.com/?url=http%3A%2F%2Fmailman.qth.net%2Fmmfaq.htm&data=02%7C01%7C%7Cf393b397c91f48af153e08d69813be04 https://eur04.safelinks.protection.outlook.com/?url=http%3A%2F%2Fmailman.qth.net%2Fmmfaq.htm&data=02%7C01%7C%7Cf393b397c91f48af153e08d69813be04
> > 
> >     >     ______________________________________________________________
>     Boatanchors mailing list
>     Home: http://mailman.qth.net/mailman/listinfo/boatanchors
>     Help: http://mailman.qth.net/mmfaq.htm
>     Post: mailto:Boatanchors at mailman.qth.net mailto:Boatanchors at mailman.qth.net
> 
>     List Administrator: Gary Harmon, K5JWK
>     ** For Assistance: gharmon at idworld.net mailto:gharmon at idworld.net **
> 
> 
>     This list hosted by: http://www.qsl.net
>     Please help support this email list: http://www.qsl.net/donate.html
>     Message delivered to cvest at cox.net mailto:cvest at cox.net
>