Will do and get back to you..
The test in post #31 is the test of these two (pic in post 31) that I found... Mosfets have three leads, no? I'm thinking the C on these is Ceramic?
Thanks again
The test in post #31 is the test of these two (pic in post 31) that I found... Mosfets have three leads, no? I'm thinking the C on these is Ceramic?
Thanks again
Yes, please post the same measurement for the 1N60C as you did with diode 503. This 503 is perfect.
I have no idea what the 'C' means.
I have no idea what the 'C' means.
Thanks.
The values differ a bit from the original but it's well worth trying. If the resistor measures 5.6k..
The values differ a bit from the original but it's well worth trying. If the resistor measures 5.6k..
OK,, 2 tornado warnings are passed, back to work!!!
Disconnected one end of R311,,, Schem says 5.6k,,, parts list says 3.3k,,, resistor in amp is 1500R (Brn/grn/red) reads 1477R...
Resistor reads properly, now what!!!?? Maybe install one of the diodes I found, and try a decade box ?
Disconnected one end of R311,,, Schem says 5.6k,,, parts list says 3.3k,,, resistor in amp is 1500R (Brn/grn/red) reads 1477R...
Resistor reads properly, now what!!!?? Maybe install one of the diodes I found, and try a decade box ?
Haha, weird schematic, part list and amp 🙂
I'd install the diode and try with the 1.5k. Nothing to loose..
I'd install the diode and try with the 1.5k. Nothing to loose..
Hi Hugo,,,
We dont have em much either, getting more and more in the last few years, tho..,,, outside Philadelphia...
Well... we got it!!!I took me a while to gain working access,,, and even longer to ensure the diode was in the right polarity... I just tacked it onto the leads from teh broken one,,, didn't want to dig it out twice!!!
I connected it to a diode box,, 3,3K,, 5,6K and 18K,,, settled on the resistor that was in it, as it gets full range,,, and dialed it in with the pot (VR-2201)
Now the next challenge with this thing!!!! Maybe scaring up a 2SB54 and getting FM MPX and light working,,,
Thanks for the help, and staying with it,, it's not done yet tho!!!
We dont have em much either, getting more and more in the last few years, tho..,,, outside Philadelphia...
Well... we got it!!!I took me a while to gain working access,,, and even longer to ensure the diode was in the right polarity... I just tacked it onto the leads from teh broken one,,, didn't want to dig it out twice!!!
I connected it to a diode box,, 3,3K,, 5,6K and 18K,,, settled on the resistor that was in it, as it gets full range,,, and dialed it in with the pot (VR-2201)
Now the next challenge with this thing!!!! Maybe scaring up a 2SB54 and getting FM MPX and light working,,,
Thanks for the help, and staying with it,, it's not done yet tho!!!
Great, I knew you would succeed! 
Maybe you can find a 2SC54 in the old Philco? What is it's type nr.?
Maybe you can find a 2SC54 in the old Philco? What is it's type nr.?
Thanks,, Guess I dont know when to quit!! Doubt it has one in the Philco, its a tube radio!!! 2SB54 Ge PNP,,, in case you run into one.. but the at least diodes were made in japan!!
I have here an AC181 which is a direct replacement. PM me your address and I'll send it to you at no cost.
But first measure diode 502 at the emitter of the 2SB54 to make sure it's OK. No need to take it out of circuit.
But first measure diode 502 at the emitter of the 2SB54 to make sure it's OK. No need to take it out of circuit.
With Netlists help, this is moving along nicely,,, I've since replaced the Suzuki oil caps and another noisy transistor, which will be replaced with a pair when the "permanent " ones come from Digi... Also found a noisy cap, and replaced the pair and got it biased... Very cool and good sounding, but somewhat odd receiver, they did it differently back then, I guess...
Was checking all the diodes this morning and noticed one 1N180 with a broken lead,,, Netlist told me 1N4148 was a replacement and I had some,, so I replaced all 4 in the bias ckt,,
Played two CDs thru it,, up to 100db! Stayed cool as a cucumber,,, bias was 14.8-9 mV when I started them, and read it again before I turned it off, and it read within a tenth!!! I think we're gettin closer,, can't imagine what it will sound like with matching, same type transistors,,, I cant wait til they get here!!!
Thanks again for all the help,, Netlist!!!!
Played two CDs thru it,, up to 100db! Stayed cool as a cucumber,,, bias was 14.8-9 mV when I started them, and read it again before I turned it off, and it read within a tenth!!! I think we're gettin closer,, can't imagine what it will sound like with matching, same type transistors,,, I cant wait til they get here!!!
Thanks again for all the help,, Netlist!!!!
Hi Hugo,,
More questions! I warmed up the receiver this morning with FM and a CD,,, and rechecked bias after it ran up a bit... The Right side was a bit low, and adjusted back to normal,, but the Left side fluctuates pretty high, sometimes over the meter setting(200mV)... I tapped components on the Left side looking for a loose joint,,, and rechecked emitter resistors which all match, at 1R should be .7R but its meter error down low... So I guess I have a bias problem since yesterday,, and not sure where to go from here... Any thoughts?
Thanks
More questions! I warmed up the receiver this morning with FM and a CD,,, and rechecked bias after it ran up a bit... The Right side was a bit low, and adjusted back to normal,, but the Left side fluctuates pretty high, sometimes over the meter setting(200mV)... I tapped components on the Left side looking for a loose joint,,, and rechecked emitter resistors which all match, at 1R should be .7R but its meter error down low... So I guess I have a bias problem since yesterday,, and not sure where to go from here... Any thoughts?
Thanks