Hi Les,I hope you'll not consider me unpolite for direct contact; You're one of the most competent and helpful person out there. I bought a Shure Unidyne 545s pistol grip. First I tested the impedance (I'm not an electronic expert) in both hi and lo-Z config (Amphenol 4 pins plug, I followed the directions on the Shure site). I was surprised to see that the value at hi-Z is only 22 ohm; at lo-Z is ... 22 ohm. I checked a Shure 99S56 SC cartridge and the result is about 1300 ohm. Then I tried to measure the output (tension) while blowing in the mic, and I had the impression that the value before the transformer was higher than the value at the plug.
Then I plugged the mic in the amp and it works, but it seems to be weak. The 99S56 is much more powerful.
Is there something wrong? Transformer not working properly (hi-Z = lo-Z)? May be some problem with polarity (the yellow and green cables to the elements seem re-soldered)? any additional tests?
Thanks in advance. Regards.