[TenTec] Model 540 Questions (Low Power TX, ALC LED, and model 244 display woes)

[Louis Ciotti]

I am continueing to unpack my ham radio gear, and I finally got to my
grandfathers model 540 (Analog dial).  I need to go through and
address the common grounding problem, but it seems to have developed
low output power on all bands.  The last time I used it was probably a
year ago and it did not exibit this symptom.  I do remember the ALC
LED blew so I know I have to replace that.  What are the specs on the
LED?  I want to make sure I replace with one that is close so I do not
have to mess with the current limited resistor on it.

On the Low TX power, into a dummy load I get between 20 and 30 watts
output.  As I increase drive it appears that output power will stop
and never increase after a certain drive level, I suspect the ALC is
kicking in, but with a bad LED I cannot verify right now.  Thoughts?

Will probably start disassembling it tonight the radio tonight.

Couple of other things.  Would TecTec be the only source for case
screws for this rig?  They seem like and odd ball type.  I must say
the RX on these older TenTec is nice, I much prefer it over my Yeasu
950 audio...

Now the model 244 digital display has degraded to the point where it
is just about useless.  Every digit has one or two segments that are
always on.  I have not dug out the schematic, but I suspect the driver
IC is going...  Anyone experienced this before?

I am also considering looking for a parts rig if I can find won low cost.

When I get all these working I have to get the external VFO working...
many projects on the bench right now....  but I am having fun!

Thanks in advance!

Lou