Howard 718

3/26/2008 2:11:15 AMJordan

been pouring over the schematic in riders for awhile now and i am still unsure of a few things. if anyone out there has restored or even seen one of these let me know. I could use all the help i can get

3/26/2008 10:25:14 AMJon

:been pouring over the schematic in riders for awhile now and i am still unsure of a few things. if anyone out there has restored or even seen one of these let me know. I could use all the help i can get

3/26/2008 10:25:52 AMJon

::been pouring over the schematic in riders for awhile now and i am still unsure of a few things. if anyone out there has restored or even seen one of these let me know. I could use all the help i can get

What are your questions?
Jon

3/26/2008 8:05:19 PMJordan

:::been pouring over the schematic in riders for awhile now and i am still unsure of a few things. if anyone out there has restored or even seen one of these let me know. I could use all the help i can get
:
:What are your questions?
:Jon

The output stage seems strange to me due to the fact that the screen voltages appear to be higher than the plate voltages. Ive always been told youll burn your tube up right away by doing that.
The next question will probably be remedial because im not looking at it right, but what is the function of the speaker tap back to the pushbutton tuners and tone and volume stack?
Third, I can see how the negative grid voltage is derived from the first diode in the 6H6 but after that the function gets murky as to whats going on detector wise. Seriously thanks in advance for any help

3/27/2008 1:24:14 AMJordan

Ok, so the speaker tap is for the nfb to pi section, but why insert it at the tone control? im used to seing it sent to the base of the ltp. However i suppose this isn't like what im normally used to seing. It seems to be a very messed up volume and tone stack also, though i guess it works alright. So im just not looking at it the right way. Also, about the function of the cap to ground right after the secondary of the last if transformer and the one meg resistor, is it simply to filter the AVC into a more constant dc voltage or does it have another purpose?

3/27/2008 7:42:08 PMJordan

anyone have any ideas?