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Harris FM-10k and 10H PA Plate Tuning control is jammed

I have a Harris FM-10k and a FM10h with jammed up PA plate tuning controls. Apparently, this is a common issue and I was wondering if there is an easy fix for it. I have a spare set of gears for the 10k tuning mechanisim assuming this is where the trouble is located. On both transmitters the "tube stub" that is moved by the mechanisim seems to move freely so I am guessing the gears are fouled up somehow.

I have not found any documentation on how this mechanism comes apart. Any advice?

Thanks!
 
Unger said:
I have a Harris FM-10k and a FM10h with jammed up PA plate tuning controls. Apparently, this is a common issue and I was wondering if there is an easy fix for it. I have a spare set of gears for the 10k tuning mechanisim assuming this is where the trouble is located. On both transmitters the "tube stub" that is moved by the mechanisim seems to move freely so I am guessing the gears are fouled up somehow.

I have not found any documentation on how this mechanism comes apart. Any advice?

Thanks!

Seriously???...

Two Different Transmitters???!!!

Assuming this is NOT a joke, I would suggest finding someone with a clue on how to operate a transmitter, before someone gets killed. It's fairly clear that someone either does not understand how to either install a tube, or tune a transmitter, and a transmitter is hardly the thing to play with, if you don't understand it's operations and dangers.
 
I've seen, on similar transmitter, the turns counter mechanism get gummed up with dust and other gunk after years of neglect. Typically a removal and cleaning of this mechanism restores the tuning back to smooth operation. Use Gun Lube/ Oil as your lubricant due to the high temperatures that can occur in a transmitter. BTW: You won't find any info on doing this in a manufacturers manual.

Lastly; If you have a replacement for the turns counter assembly I'd suggest just replacing it completely.
 
I just had to replace the "rubber band" on one of our FM25k's Not sure if the 10K has the same design, but the symptoms sound similar. An easy all be it $$ fix.
 
Yes two transmitters, a main and backup. I inherited them this way when I took the job. Just simply looking for someone who has done the procedure before on this specific transmitter that might have an insight so that I can plan properly. They are built almost exactly the same in the tuning area so I assume this is a common issue. Thank you for your concern but I am experienced and competent.

Thank you.

Burley
 
Unger said:
Yes two transmitters, a main and backup. I inherited them this way when I took the job. Just simply looking for someone who has done the procedure before on this specific transmitter that might have an insight so that I can plan properly. They are built almost exactly the same in the tuning area so I assume this is a common issue. Thank you for your concern but I am experienced and competent.

Thank you.

Burley

Sorry I came on a bit strong....sometimes we get folks who don't know any better asking questions, so it's a little alarming when one sees such obvious abuse, and sometimes advising someone who really doesn't know, can be real dangerous.

OK, assuming you have an idea, you likely have to get the transmitter in a somewhat tuned position, which means a lot of on off, adjust, the more of the same manual tweaking...

when it is close to where is has to be, make sure it's "somewhat centered" clean and lightly lubricate the knobs, counters, screw, and make sure you clean the gunk off the bearings. Make sure the oil does not get on the actual tuning components, and graphite is a definate no no.

There are usually set screws, make sure they are tight, but not stripped, if they are stipped, you really need replacements, I have see folks who drilled them, and stuck something thru them, but that's a last resort.

Work the tuning to get it right, and don't be surprised if you have to do it several times, once you have it right, just remember that you can't force tune it, it only goes so far.

Clean the transmitter occasionally, and put a drop of oil on the front and back bearings, that's normally where the dust and stickiness comes in. If it's clean, and not forced, you won't have an issue
 
Burley (and others):

Parted out the 10K I had in my garage (if you are who I think you are--that's the one the plate transformer came out of for your 10H.

The one thing I don't think I have is those tuning linkages. But have contactor, rectifier stack, choke, & small parts on that left front door.
 
TomT said:
Burley (and others):

Parted out the 10K I had in my garage (if you are who I think you are--that's the one the plate transformer came out of for your 10H.

The one thing I don't think I have is those tuning linkages. But have contactor, rectifier stack, choke, & small parts on that left front door.

Hi Tom! Do you still have the PA filament transformer? It would be nice to convert our 10H to accept the 4CX10000J.

Burley
 
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