NC-183D schematic please

[AB3FL]

I have just acquired an NC-183D in very good condition.  I downloaded the manuals from BAMA and they look OK.  Does anyone have a GOOD, CLEAN copy of the schematic not split into two pages or even two pages is OK if it is straight.  The BAMA one is skewed.

thanks

Tom - AB3FL

[WQ9E]

Tom,

Check and see which version of the NC-183D you have.  One uses a 6J5 as the phase inverter while the other has a 6SN7 with one section used as the phase inverter and the other used as an amp in the S meter circuit.

Also make sure your receiver doesn't have the .1 cap from one of the rectifier plates to ground, it is a good transformer killer.  It isn't needed so just clip it out if it is in place.

[AB3FL]

Phase inverter is a 6SN7.  The schematic I have from BAMA shows the 6J5.

thanks

Tom - AB3FL

[WQ9E]

Tom,

Mine is also the 6SN7 version.  Attached is a less than perfect electronic version but hopefully it helps.

[AB3FL]

Tom,

Mine is also the 6SN7 version.  Attached is a less than perfect electronic version but hopefully it helps.

Thank You very much.  That will work

Tom - AB3FL

[WQ9E]

My NC-183D had more out-of-spec resistors than any other piece of gear I own.  Every 47K screen dropping resistor in the RF and IF sections was several times its marked and rated value.  I am suspicious mine was built with mis-marked components since they were all very consistently high and the original owner noted in the manual that he had rewired section 1-A of the bandswitch so that it ran at maximum gain on all bands to overcome low sensitivity problem.

Properly operating it is a good receiver.  It sounds great on AM and the calibration is good.  When I bought my NC-400 I assumed it would be a "super NC-183D" and it is in most ways but the NC-183D frequency stability is better on the higher bands.