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THE AM BULLETIN BOARD => Technical Forum => Topic started by: n4wc on December 30, 2008, 05:35:45 PM



Title: What Tube is it?
Post by: n4wc on December 30, 2008, 05:35:45 PM
I have a RCA electron tube #7358.  It looks like a 6146 type.  Inside the octagon on the glass is 7358 and below it is PDA.  On the metal base is made in USA 59-39.  Does anyone know what the specs are?


Title: Re: What Tube is it?
Post by: W3NP on December 30, 2008, 06:10:42 PM
The RCA transmitting tube manual lists it as a beam power tube for use as a rectangular wave pulse modulator. All of the ratings are based on duty factor and average "on" interval.


Title: Re: What Tube is it?
Post by: Tom WA3KLR on December 30, 2008, 08:00:58 PM
The release date is May 1959.  The "59-39" is probably the date code for 39th week of 1959.


Title: Re: What Tube is it?
Post by: WZ1M on December 31, 2008, 03:37:26 AM
Beam power tube. T-12 bulb. Pulse modulator. 6.3 volt @ 1.25 amp heater. 3.5kv, 10 watt. Made by GE and Sylvania, may of 1959
Gary


Title: Re: What Tube is it?
Post by: n4wc on December 31, 2008, 03:48:37 AM
I think I had this in an Eico 720 back in the sixties.
Thanks for the info.
I'll have to scrounge around for a RCA transmitting tube manual ;-)


Title: Re: What Tube is it?
Post by: WBear2GCR on December 31, 2008, 08:15:54 AM

You can find them in pdf for download online... google is useful for finding these things...

             _-_-bear


Title: Re: What Tube is it?
Post by: W3NP on December 31, 2008, 09:02:02 AM
I think I had this in an Eico 720 back in the sixties.
Thanks for the info.
I'll have to scrounge around for a RCA transmitting tube manual ;-)

Do you still have a rig that uses a single 6146? It looks like this tube would work. Basing, Mu, Transconductance, inter-electrode capacitance are all identical.

You probably did use it in the 720.


Title: Re: What Tube is it?
Post by: W3RSW on December 31, 2008, 10:39:34 AM
Yeah, it sure sounds like a 6146 relabeled, possibly "ruggedized" and sold for three times the price  ;D

"If it walks like a duck....
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