FT-901DM Rectifier "A" Board PB1708A

Discuss anything related to any of the Classic Yaesu Transceivers

Moderators: KE7GUY, KC9FOZ, EA5/G0KOM, KG6JEV

FT-901DM Rectifier "A" Board PB1708A

Postby WA7BZI » Thu Nov 02, 2006 5:18 am

The FT901DM I bought new in 1978 and have had in storage for several years decided to burn up a couple of resistors, R1003 that's located between the four small ELNA 22uF/250v caps on the Rectifier "A" board (PB1708A), and the striped 1/2 watt resistor (value and P/N unknown) that's mounted vertically near the outside edge of the board. There's a R1002, 5.6K resistor that's OK. The four caps have a very minor amount of cap cheese around the base... just curious if Yaesu still has these boards available, or if the Candy Store might have exact replacement components. Luckily I didn't encounter any "exploding" caps, just the main 5amp power fuse blew. The diodes all look fine, but probably should test them. The Rectifier "C" board (PB1717A) also looks fine, but since these caps are aging, probably should replace them too just to be on the safe side.

I'm new to the user's group... what a wonderful find!

Any help would be appreciated. BTW, my rig's S/N is 8H050010.

TNX.

John/WA7BZI
WA7BZI
 
Posts: 2
Joined: Thu Nov 02, 2006 4:58 am
Location: Seattle, WA

Postby WA7BZI » Thu Jan 04, 2007 9:22 am

Gee gang, I can't believe nobody has responded to this by now. Is it no interest or a no brainer! Still looking for a source for the parts and a schematic, as I can't find my manuals. Help appreciated! TNX.
WA7BZI
WA7BZI
 
Posts: 2
Joined: Thu Nov 02, 2006 4:58 am
Location: Seattle, WA

FT-901

Postby PA0PGA » Thu Jan 04, 2007 9:26 pm

John,

For the manuals you can look in the Fox-Tango site, they are downloadable from the library.
About the caps: Some look if they have capacitor cheese around the base, but they have also a tough brown stuff around them that Yaesu used to fix the caps to the board.
If you change condensers: Look that you get high-grade caps with the same or higher working voltages and for a higher temperature.
Because modern parts are almost always smaller than the previous ones, it is no difficulty to obtain the right caps.
About the resistors: It is best you get yourself the Service Manual from the library, it has the board layouts, parts list and so, all you need to perk your 901 up.
There is even a Survival Guide for the 901, so enough reading to do.

Hope this helps, saw your entry just today....

73, Wim PA0PGA
User avatar
PA0PGA
 
Posts: 52
Joined: Tue Jan 03, 2006 9:59 am
Location: Geulle


Return to HF Transceivers

Who is online

Users browsing this forum: No registered users and 1 guest

cron