Sony KV-2643R score

[freakaftr8]

Somewhere I have a Simpson model 303. IIRC, it worked ok, but had a sticky needle that I repaired some years ago. Would the DVM meter be a bad choice because of the frequency the flyback runs off for the ripple in the DC that DVMs cannot pickup?

[maxhifi]

Originally Posted by freakaftr8

Somewhere I have a Simpson model 303. IIRC, it worked ok, but had a sticky needle that I repaired some years ago. Would the DVM meter be a bad choice because of the frequency the flyback runs off for the ripple in the DC that DVMs cannot pickup?

They run the filament off high frequency AC, not DC. A DVM usually starts to read low as frequency increases, getting grossly inaccurate by the time you get up to approx. 15kHz (flyback frequency)

Someone correct me if this era sony doesn't power the filament this way, but I'm pretty sure they do. At one point you could buy Sony specific brighteners, which were small high frequency transformers intended to boost the filament voltage off the flyback.

Here is an example https://www.ebay.com/itm/SPB2-ISO-Is...-/182417131479

Before proceeding, make sure the filament in this TV really is powered from the flyback