DOES EVERY VALVE NOTATION WITH THE CHARACTERS X4 EXCITE YOU?
Posted by STEVE M on
When posing this title question, I was reminded of an event that happened a few years ago at the NVCF. I was attempting to sell for a good friend and BVWS committee member both an AVO VCM163 valve tester and a globe Osram PX4.
A potential Italian customer sidled up to the stall, going into raptures about both items - his eyes were bulging and there was a sheen sweat on his top upper lip as he recited the valve pin settings for a PX4, well we all know 8423000000 don't we? Certainly it resulted in the owner of these items being totally nonplussed especially when asked for a sizeable discount.
As we all know, the PX4 and indeed its larger brother, the PX25 are sought after devices and command significant sums especially in the globe envelope configuration, but what about other valves that have the X4 notation in their descriptor?
Ladies & Gentleman ( and Agender, Androgyne, Bigender, Butch, Cisgender, Gender expansive, Genderfluid, Gender outlaw, Genderqueer, Masculine of center, Nonbinary, Omnigender, Pangender, Transgender, Trans, Two Spirit, or indeed any other gendah!), I give you the TX4.
The TX4 has a few pros and cons when compared against the PX4, firstly, a good example is about 40x cheaper than a PX4. Conversely the con is that rather than being an audio power triode on a B4 base , it is in fact a triode-hexode on a B4 base. The TX4 notation was unique to its manufacturer - Tungsram and there are a few rather more familiar equivalents known: -
