The AM Forum

THE AM BULLETIN BOARD => Technical Forum => Topic started by: K2GTM on February 10, 2017, 11:26:28 AM



Title: Name that Eimac!
Post by: K2GTM on February 10, 2017, 11:26:28 AM
Hello all,

I have this Eimac tube - new, sealed in the original box. (See photo.) The only marking is "1ADTH" on the outside. I'd hate to open it up since it's so nicely sealed-up. Anyone have a guess as to what's inside? I've never heard of a "1ADTH" before.

Thanks and 73,
Greg K2GTM


Title: Re: Name that Eimac!
Post by: Todd, KA1KAQ on February 10, 2017, 12:59:34 PM
Size-wise it looks like a frame-mounted 250TH or similar. They used the same shipping racks for 250TH & 450TH, maybe 100TH as well. The 1AD is likely a commercial or military designation of some sort. For example, I've seen 100TH tubes with JAN-C1M-100TH on the box.


Title: Re: Name that Eimac!
Post by: W7TFO on February 10, 2017, 01:18:41 PM
For example, I've seen 100TH tubes with JAN-C1M-100TH on the box.

That would be CIM, the JAN designator for Eitel-McCoullough. 

All tube manufacturers codes were alpha characters, i.e. CRC for RCA, CNU for National Union eTc.

I'd open that box right now and enjoy whatever it is!

73DG


Title: Re: Name that Eimac!
Post by: Opcom on February 10, 2017, 05:14:58 PM
aargh.. too bad my x ray machine is not working!!
Not that shipping it would be a great idea.

Have you tried contacting Eimac/Varian/Econoco? a long shot.


Title: Re: Name that Eimac!
Post by: W7TFO on February 10, 2017, 05:35:51 PM
Upon second look, I'm willing to bet that stencil actually says "100TH"

73DG


Title: Re: Name that Eimac!
Post by: KA0HCP on February 10, 2017, 07:21:40 PM
"IAD" is the airport identifier for Dulles International.   Note the recipient address in adjacent Falls Church, Va.  

I checked my Eimac 1948, 53, and 1955 catalogs and they have no product "1AD".

Go ahead and open it up.  That doesn't hurt my historic sensibilities.  :)  bill


Title: Re: Name that Eimac!
Post by: WD5JKO on February 10, 2017, 10:27:23 PM
aargh.. too bad my x ray machine is not working!!

I think Wilson is inside. Tom Hanks has a reward out for him...

Jim
Wd5JKO


Title: Re: Name that Eimac!
Post by: K2GTM on February 10, 2017, 11:36:55 PM
It actually looks like someone removed at least one sticker from the outside of the box.  Probably the one that had the actual part number on it! 

Yeah, I was afraid I was going to have to open her up to find out.  Oh well...


Title: Re: Name that Eimac!
Post by: AB3L on February 11, 2017, 10:23:20 AM
You could photo document the unveiling...


Title: Re: Name that Eimac!
Post by: W3RSW on February 11, 2017, 12:54:50 PM
No wait, still more sleuthing required by the gangstas.

Dulles was probably not yet built when that box was mailed. Where are the REA stickers?
 ;D


Title: Re: Name that Eimac!
Post by: ae7db on February 11, 2017, 02:20:08 PM
I believe Dulles opened in 1962.  The 5-digit zip codes were introduced in 1963, so the package was shipped after that.

Dean


Title: Re: Name that Eimac!
Post by: K2GTM on February 12, 2017, 09:39:48 AM
I opened it very carefully, and....

It's a 3-500z! Dated 7610 (the week before my birthday).

Thanks for playing, everyone.  😊


Title: Re: Name that Eimac!
Post by: KD6VXI on February 12, 2017, 11:18:59 AM
Wow,  what a cool surprise!

--Shane
KD6VXI


Title: Re: Name that Eimac!
Post by: W3RSW on February 12, 2017, 06:38:22 PM
Yeah, what a neat find.  ;D
Tnx for Dulles info. Didn't  realize it was that old. So Falls Church from IAH wins it.

& Well! A whole new conundrum.  Do you open the inner box now and properly getter it after all these years for use, or let it remain unopened for many more years?

Gotta protect that yellow box regardless.  Back in the magic shipping container for resealing she goes.


Title: Re: Name that Eimac!
Post by: N8ETQ on February 12, 2017, 07:14:59 PM




   I guess the "Clue" would have been "Eimac".
When did they change the name?  Here is a Korea era
jug in original box.

   It takes "Stones" to pop something like
that.. Gud Man!!!!


/Dan





Title: Re: Name that Eimac!
Post by: N8ETQ on February 12, 2017, 07:24:06 PM


   BTW...


        Here is a 250 TH Frame Racked In the box.
Korea Era too..  To Big for my scanner..


   See'in as how they are clearly labeled
no need to open em', Till I need to open em'!


/Dan




Title: Re: Name that Eimac!
Post by: K2GTM on February 14, 2017, 06:35:15 PM
I'm not opening the yellow box - I like keeping it sealed-up for posterity sake.   :) 

I'm debating what to do with it...  I don't really have a use for it at the moment, and could always use the money. 


Title: Re: Name that Eimac!
Post by: Opcom on February 14, 2017, 09:09:40 PM
This was fun! good find too. There's one of those 250TH spring boxes here with tube - it was used to ship a couple of those tubes to me and holds the un-installed one.
AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands