Knight 600 Valve Tester demo: Mullard NOS ECC83 Part 2

1 year ago
7

This is a demo of my Knight 600 valve tester with 3 NOS Mullard ECC83as test subjects.

I wanted to try out some valve testing as I have valves from different suppliers here in the UK and all have different measures of performance. Hotrox, Watford Valves and Karltone all supply valves with non standard measures of match.

This may not be an issue for complete sets but given the problems with valve supply these days, it might be nice to swap out one single valve from a Hotrox set with one from Watford for example and there is no correlation between the two suppliers.

So I bought a valve tester. Now this one is not the one for the job as it is a simple emissions tester and won't measure transconductance or any other parameter related to bias. It is however, a nice wee tester that I found on ebay. The seller told me it was 240V but it wasn't. It had a a US 2 prong plug on it!

So this was swapped out for an earthed US plug and I bought a step down transformer to supply it with the US voltage.

It actually was calibrated too! I get 6.3V between pins 2 and 7 of the 6V6/6L6 octal socket with the line adjust set to put the needle on the exact midpoint of the meter. That's all you can do apparently and I tested these 3 old Mullard valves in this video. No need for matching with these but it can be good to know the strength of each triode pair in the glass bottle and see if both are matched together for Phase Splitter use (even if it's not really important in valve amps)

I have an AVO Mk3 characteristic meter and I will do a demo shortly of this more scientific tool which can grade and match valves.

Please visit my website for more cool stuff: https://www.gringopig.com/

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