IFR 1200S service monitor/spectrum analyzer issue

[Radio Tech]

I been searching the web looking for answers but are very limited, so was wondering if anyone has ever worked on one of these units. I have had this piece of equipment for many years now.  I know there is a place called KG Electronics that work on these. But since he is in the business he does not give out information.  So with that here is what is happening.

A year ago when I power the unit, the lock light would just flash. Turn the unit off and back on and then the light locks. Sometimes I turn it on and it just flash but will go to lock by itself after a short while.
A few months ago I noticed that sometimes when switched to spectrum mode, the trace on the CRT disappears, or the noise floor is way below the bottom of the window. I can switch back to scope mode and the trace is fine. Sometimes I can play with buttons at random and it will just pop back to normal.

Yesterday I walk in the shop and power it up; I got a checksum error followed by memory reset.  I hit the RF key and all goes back normal. I confirmed this is happening each time it is powered up now.

From what I can see the generator is working properly and I see no other faults other than what I described. The only thing close on the web I could fine was a shot blog on a checksum error and a faulty spectrum display.

I have not torn into it yet but from what I am seeing I am thinking power supply issues. This piece does have some age on it now and we now caps dry out.
Do you think this would be a logical analysis?

[KJDS]

There's a service manual here

http://www.repeater-builder.com/test-equipment/aeroflex/ifr1200/ifr-fm-am-1200a-ifr1200s-service-manual.pdf

[Radio Tech]

Thanks, I do have the 3 ring binder manuals here. But hey, an electronic copy sure saves space.
I am gong to take this puppy apart friday and see if I can spot something that stands out. Look for hot spots so to say.