Radio Road

Posted by low_budget_listener (A) on February 21, 2010 at 08:03:33

In Reply to: RE: Yamaha T-80 pulling in more stations than T-85 !!?? posted by mcgjohn@yahoo.com on February 20, 2010 at 10:12:47

Thanks for the Vishay resistor link. Eventually, I'll probably consider tinkering with the resistors, after everything else is finished. To be honest, my head already feels like it's going to explode, and so far I've only considered replacing the caps and some diodes in the power supply.

I've never used schematics before, and there's so much information (much of it conflicting) about capacitors on the web that just when I feel like I'm getting a handle on it, confusion washes over me again like a tidal wave, and my confidence subsides. I've put together a list of all the caps used, but now I have to measure the actual voltage across each, and the physical dimensions, including distance between the leads. I think I'll play it smart, and invest in a cheap non-conductive ruler...

About the lack of signal:
I was using a dipole directly into the T-80, and since the T-85 didn't have 300 Ohm terminals, I used a balun on the dipole into the 75 Ohm terminal. Adding a splitter eliminated the balun as the cause of the problem (it's between the dipole and the splitter, and therefore impacts every tuner I connect), and I no longer have to swap the antenna back and forth. I do side by side comparisons by hooking up two tuners at the same time to different inputs on my preamp.

The T-80 had already been sold, but once I had the splitter hooked up, the first thing I did was swap leads between tuners, pitting the T-85 against my other two remaining tuners. The T-85 grabs fewer stations than either of the other two.