[time-nuts] OT - Tek 7L18 ROM

[Christopher Hilton-Johnson]

>Hello all,

>I have an old 7L18 spectrum analyzer that used to serve me well on the 
>higher bands.
>Unfortunately, the controls have got into complete disorder.
>It seems like one or both of the ROM's are dead.

>Anyone have / knows where to find ROM images of the 7L18?

Adrian
Can I suggest you post this to the tekscopes group - they have answers
to pretty well everything Tek
Having said that I do not know of any ROM images out there - I have 2
7L18s but have never got around to making ROM backups - never been able
to find the ROMs to burn.

Assuming it is the digital section at fault (eg no panel controllable
frequency on the readout display)Several pointers;
1) If not used for a long time, the connectors, both internal and to the
mainframe can go very dirty.  The PI uses lots of power & needs every
connector to be doing its job.  Some users say remove & slam in the PI
several times to help wake it up (very brave/stupid ones do it with
power on)
2) digital parts can be affected by gone bad electrolytics pulling down
the supplies or eg: affecting the processor reset circuit.
3) in my case the processor board had a defective RAM - no response to
controls because no boot, although it would get to different stages of
the boot process before halting.  (Got a replacement chip from that
auction house)
4) because the various sub sections/boards are so interconnected the
best way to trouble shoot is to have a 2nd 7L18 (or at least a second
processor board)available for board substitution.
5) you can make extenders which allow board level trouble shooting - the
digital bit runs quite slowly and a logic analyzer will help if the
problem lies further down the line.
6) finally, if you can back up the ROMs, I would like to place an order
for a set!

Chris HJ