Tube Data

[Bygar]

Specification sheet desired (required) or copy.
For the following CRT: WX5013 P1, Westinghouse Electronic Tube.
Thanks Bygar

[rshayes]

The only Westinghouse CRT that I ever encountered was a WX5078P1. This was used in the EICO Model 435 oscilloscope, a kit oscilloscope sold in the 1960's.. It was a 3" flat face electrostatic deflection type.

I have never been able to find a data sheet on that CRT either. I have also never seen a list of Westinghouse CRTs or any indication that Westinghouse had a facility for manufacturing CRTs.

This is pure speculation. It is possible that Westinghouse made some instrument that used these CRTs and had a special order produced to their specifications by some other company. The remainder of the production run could have been sold to EICO as surplus. Heathkit started out using surplus parts from WW II, and was still using surplus CRTs (originally supplied to the Canadian armed forces) in the early 1960s.

[Dean Huster]

Check out the appendix of older Radio Amateur's Handbooks(ARRL), maybe between 1960 and 1980 editions, as they had CRT data for easily-available, popular CRTs of the time.

[rshayes]

Dean- That was a good suggestion. Unfortunately, the ARRL apparently does not believe in CRTs. The CRT table in the 1960 edition was rather short (about 3/4 page) and after 1968 the CRT data table was deleted entirely. A few CRTs had base connection diagrams but no characteristics after 1968. None of the tables list any CRT with a WX prefix.

I have a CRT from an EICO Model 435 Oscilloscope that is clearly labeled WX 5078P1. Poor printing, or erosion of the label might make the number appear to be WX 5013P1.

A google search on WX5078P1 resulted in one hit on another bulletin board that suggested that the tube might be equivalent to a 3AQP1. This may be correct.

The envelope dimensions and base connections appear to match either the 3AQP1, the 3RP1, or the 3RP1A. The WX 5078P1 has a flat screen, as does the 3RP1A. The 3AQP1 and the 3RP1 have spherical screens. The 3RP1A appears to be a physical match.

Electrically, the 3AQP1 and the 3RP1 differ in the deflection sensitivity of the D3 and D4 deflection plates (farthest from the screen). In the 3RP1, both sets of deflection plates are nearly equal in sensitivity. In the 3AQP1, the D3 and D4 plates are more than twice as sensitive as the D1 and D2 plates. In the tube that I have, the rear deflection plates appear to be exceptionally closely spaced (well under 1/10 inch), which would give these plates higher sensitivity. This sensitivity can be traded for bandwidth and the Type 435 had exceptional bandwidth (about 4.5 MHz ) for this class of oscilloscope.

I have found no listings for a 3AQP1A, which would be a flat screen version of the 3AQP1.

As a guess, the WX 5078P1 might be a special order tube using the gun assembly of the 3AQP1 in the flat screen envelope of the 3RP1A.

[rshayes]

The tube that I have is labeled WX 5078P1. It came out of an EICO Model 435 oscilloscope, and all of the documentation on that model indicates that it used a WX 5013P1. I suspect that the tube that I have is actually a WX 5013P1 and that it was mislabeled by Westinghouse.

[Bygar]

Thanks for the encouragement.
I found a site that lists the CRT for EICO model 430 which
may be the generic number 3DEP1.
I would like to find the data for same. I have good article
to build a portable scope.
Hope someone has the data.
Bygar

[Bygar]

RE: WX5013P1, Did they possibly use a date coding system on these ol CRT's.
E. G. 50 was the year 1950, 1, the month. date.

rshayes: Do you have documentation for the EICO Model 435 scope?
If so could you possibly scan it and send a PDF copy.
If so please advise. Thanks.
Found some data project can now proceed.

[rshayes]

The tube that I have appears to have a date code. It is stamped "68 22", which I assume means the 22nd week of 1968.