Found it will post in case any one else needs it

*Subassembly: *Output Unit 1.5 GHz**

*Stock No.:    *1038.7909.08 for SMT, 1038.7909.10 for SME**

*Action:               *2 - Modify in the case of repair**polarity.

Subassembly: Output Unit 1.5 GHz
Stock No.:    1038.7909.08 for SMT, 1038.7909.10 for SME
Action:    2 - Modify in the case of repair

Modification: Replace capacitor C807 by a new one. Connect the positive
electrode to ground and the negative electrode to the —5V supply
voltage. (1038.7909.01 S, page 9, location A4)

Change the fitting of the coding resistors for revision 6: R10 not
fitted, R11 fitted, R12 fitted, R13 not fitted (1038.7909.01 5, page 2,
location D4).

Check the displayed revision REV 6 of module OPU1 of the instrument
(menue UTILITIES — DIAG
CONFIG).

Reason:    The capacitor 0807 was fitted with wrong polarity. Circuit
diagram and fitting design show this wrong polarity.


Type: SME; SMT
Modification from series (last numbers on barcode label):
1038.7909.08 (SMT) 06 1038790910 (SME) O7

Calibration after modification necessary:
Subassembly: Output Unit 1.5 GHz
Stock No.: 1038.7780/1038.7909
Action: 2 - Modify in the case of repair
Modification: 1. Replace transistor V602 (part nr. 0801828300) by a new
one, even it it
seems
to be in good condition.
2. Mount sheet metal cooler (part nr.
1038797300) to improve cooling of V602
(see enclosure)
Cut a hole in the adiacent shielding wail, 7mm from the upper edge of
the module (referred to outer surface of the shielding) and time below
the edge of the shielding wall.

Attention: Be carefull, a small metal parts come out.
Put heat conducting paste on V602 for a good heat conduction.
Mount the cooler. Fix cooler with screw M2 x 5 and washer.

3. Print a "C“ beside the barcode label (with waterproof marker) to mark
the modification.

Reason: The transistor V602 is run with a high bias and therefore high
temperature. Maximum ratings are not exceeded, but lifetime is reduced.

Error code “110,
Output unleveled; ALC failure“ appears in the mixer range (up to 130
MHz, depending on model and modulation) when V602 is loosing gain. Due
to internal structure, the do bias may be maintained even When gain is
greatly reduced. Measuring dc bias therefore is no proof for a good
working transistor. To extend lifetime, a cooler is necessary to conduct
heat to the shielding.