Kenwood TS-790A Light Replacement

 I noticed a while back that my TS-790 meter displays had gone dim.  While I had the radio opened up to adjust the master clock. I decided to replace the burnt out incandescent lights with new white led lights.

I neglected to take any pictures until after the work was done, but this will show where the lights are located, and which led bulbs I used to replace them.

To access the 3 bulbs for replacement, I removed the top cover.  This and the bottom cover had already been removed in a prior repair in my case.  So I don't know if the bottom cover needs to come off or not.

There are two screws on each side of the front faceplate.  I removed the top screw and loosened the bottom screw to allow the faceplate to tilt forward off the edge of the bench.

 
Faceplate Screws

 

Be careful when tipping the faceplate forward.  I managed to break one wire out of a connector on the bottom right side.  I was able to reattach the wire with the faceplate open.  It had just gotten hung up on the chassis, but was still long enough to reattach.

The lights for the sub meter are on the right hand side.

 
Sub Meter Light Locations

*** Edited to add detailed picture of Sub Meter LED wiring 14JUN2024 ***


The lights for the main side are on the left hand side.

 
Main Meter Light Location

*** Edited to add detailed picture of S-Meter LED wiring 14JUN2024 ***


Both sets of lights are press fitted into rubber holders.  I was able to pull on the wires on the back of the lights and the bulbs will slide out.  If the rubber holder happens to slide out, it can just be reinserted and engaged like a grommet with its ring surrounding the hole it came out of.

I bought some new leds from Amazon.  They already have appropriate sized resistors installed in one leg to drop the voltage from the 12 volts supplied.  They have a concave face and 120 degree viewing angle, to reduce the "hot spot" problem often associated with led lights.

 
New LED Lights

Here are the old bulbs after removal.  They were all burned out.

 
Old Bulbs

And here is the newly lit main meter after replacement...

 
Main Meter Lit

And the Sub side meter is here...

 
Sub Side Meter Lit

The sub meter has a little bit of a bright spot, but is totally usable.  Before the repair, it was pretty much unreadable.



 


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