[ARC5] [Milsurplus] Tube Tester

[Kenneth G. Gordon]

On 12 Jul 2009 at 14:12, Bob Macklin wrote:

> The Heath TC-2 and TC-3 are really the same unit except the TC-3
> handles tubes that were non-existent at the time the TC-2 was
> produced. For an emission tester both of these units are just fine.
> Many were used in Radio/TV shops in the 50's and 60's.

Bob:

The Heathkit model I am talking about is NOT simply an 
emission tester: it is a full-fledged Dynamic Mutual 
Conductance (DMC) type.

I am not sure of the model, but it IS one of the TC-* 
models. 

Possibly the TC-1 (?)

I don't know, but I DO know that Heathkit sold at least ONE 
tube tester that was a Dynamic Mutual Conductance 
type...somewhat like the Triplett 3444 which I have, or the 
military TV-2, of which I have two (one working), or the 
Hickok types that sell for so much money on eBay.

In fact, even Eico and most other kit manufactuers, sold 
DMC types. The Eico 666 is one such for instance.

Most tube testers are, as you say, emission types, which 
except for their being faster and easier to use, are hardly 
any better than a good multimeter, coupled with a power 
supply, and a good understanding of how to measure 
things.

Also, unfortunately, many so-called Dymanic Mutual 
Conductance types are not very effective as the test 
voltages and frequecies are too low or too limited.

The I-177 is a military version of the Hickok 600 series, I 
believe, and is quite good.

Later models of the TV-2/U are also quite good. The early 
models suffered from un-wanted oscillation under certain 
test conditions which could ruin either or both the tube 
being tested AND the internal rectifiers.

My first model TV-2/U cannot test VR tubes without going 
nuts. I have ruined both the 83 and the 6X4s in it by 
attempting to test VR tubes.

In later model TV-2s, ferrite beads were installed on nearly 
every wire and connection in the beast, and that fixed the 
oscillation problems.

The TV-2B/U is a good one, although ALL the TV-2s are 
somewhat slow to use since the operator can set or adjust 
nearly everything in them...and, in fact, must for each 
change of tube type.

Ken Gordon W7EKB