[Boatanchors] compairson of 5R4 tubes

[mac]

Used them all interchangeably and can't say I've had trouble with any  
of the tribe.

Dennis D.  W7QHO
Glendale, CA

****************
On Dec 30, 2012, at 10:33 AM, Richard Knoppow wrote:

>
> ----- Original Message ----- From: "John King" <k5pgw at yahoo.com>
> To: <boatanchors at mailman.qth.net>
> Sent: Sunday, December 30, 2012 6:36 AM
> Subject: [Boatanchors] compairson of 5R4 tubes
>
>
> I note that there are various 5R4 tubes with different letters after  
> the 5R4, which I suspect refers to the bulb shape, height or other  
> style designations. I am going to order a number of 5R4 tubes for  
> older transmitters such as DX 100s and early Viking transmitters. Is  
> there any difference other than style between the various 5R4 tube  
> versions? Some versions are significantly cheaper than other  
> versions. What are your thoughts regarding the best bang for the  
> buck for these old boatanchor transmitters? Thanks and 73, John, K5PGW
>
>    I can't find complete data on the type in my tube handbooks but  
> there were at least three variations:  5R4GY, 5R4GYA, 5R4GYB, and  
> the familiar 5R4WGB. The first three are in semi-pear-shaped  
> envelopes with low-loss mica-filled bases, the WGB is in a special  
> high-altitude envelope with a large gray base and heavy tubular  
> envelope.  These were designed to work up to 100,000 feet.  The W in  
> any receiver tube type number indicates it was supplied to a  
> government contractor, there is no consistent meaning other than that.
>    My experience is that the WGB is the most common and cheapest,  
> the original brown-base GY the hardest to find. Any will work in the  
> same socket.
>    My experience is also that I've had more trouble with the WGY  
> than with the others.
>
>
> --
> Richard Knoppow
> Los Angeles
> WB6KBL
> dickburk at ix.netcom.com
>
>
> ______________________________________________________________
> 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
>
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer at usol.com **
>
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html