HP 8415 with problems

[joaquin]

Hi from Spain:

Today I had a problem with my loved HP 8415A.

Here are the details:

All is beign OK and suddenly the coils had phase -90 like a capacitor,
and since a time later the light of searching in the front (Phase
lock loop) always is active and fluctuating,

When this ocurred I was adjusting a coil for an antenna tuner, without
any tension , I only had the coil.
I will be very grateful if some expert would can give me some guide
before starts my repair work.

Thanks in advance.

Joaquin.

 

[joaquin]

I am sorry I did a error . I wrote 8415, it is 4815 a RF Vector
Impedance meter