[Premium-Rx] WJ-8711A Encoder Issue Update

[Gore, Greg]

Thought I should update the list on my progress in case I have some incorrect info and someone may catch it. I am attempting to get in a position to check out a Watkins Johnson 8711A and my first observation was a loose tuning knob which seemed about ready to fall off. The receiver otherwise looks to be in excellent condition, with good straight sheet metal and is clean inside. The previous owner sent me pictures of the display showing BITE PASS so I may have something here worthwhile to pursue. I don't have any experience with Watkins Johnson equipment yet, this one being my first and I thought I should proceed cautiously and ask questions first before I break something trying to get it apart. I was originally concerned about not seeing any setscrew holes in the tuning knob so I suspected it must be a push-on design but since it didn't move with cautious pulling force I decided to ask before going further. I also researched the archives a little and discovered Steve Pappin has posted about this a couple of times before. Apparently the encoder with the plastic shaft was an update to address noise and the "D" cut ?plastic shaft requires a push-on style knob. I received some replies that there should be setscrews in the knob but I suspect this style of knob retention was used for metal shaft encoders.


My encoder is labeled: HRPG-ASCA #F19 followed by a 4-digit date code. In researching this a little it looks like the encoder was manufactured by Avago Technologies and then checking Mouser I discovered it is still available for around $30 so I ordered one. Should be here in a couple of days and will be interesting to see if it is in fact the correct replacement encoder. I'll proceed with checking out the 8711A after I get the encoder issue squared away.


73, Greg

WA1KBQ