Rohde & Schwarz SMIQ03B with Error 110 Output unleveled; IQMOD: ALC failure

[drhex]

Probably same process as getting from 02B to 03B - you just need a factory install key. Can probably be reverse engineered somehow. Do you have info on the 6L variants? SOme around for parts on the Bay...

[Jarek]

Angielski

I also have a problem with SMIQ03
I have IQ Modulator version A240.1084.98.00.06
This is different than the ones described in the posts.
Here are the transistors marked as( .H1 ) .  There are three of them in series under the radiator. The casing is as in the photo.
What kind of transistor is it? Does anyone have a diagram of this version of IQ Modulator?

[drhex]

Schematic I have is for 1084.9800.01S. V102 is in there as SHF-88. Parts list for 1084.9800.01SA shows it as SHF-O186K4230TR made by Stanford

Mine failed after sending it out to calibration. Soldering in another switch didn't resurrect it so bought another modulator and calibrated it myself. Worked reasonably well, +.5dBm off over the whole amplitude and frequency range. Can live with that.

[Jarek]

Thank you Drhex
You're right, it's SHF0186.
My module gets very hot. I am looking for damaged elements.

[drhex]

I have a few more or less broken modulator boards here in case you're interested.

[Qw3rtzuiop]

What kind of transistor is it? Does anyone have a diagram of this version of IQ Modulator?

Take a look here:
http://www.ko4bb.com/getsimple/index.php?id=manuals&dir=Rohde_Schwarz/Rohde_Schwarz_SMIQ

[Jarek]

Thank you for the offer Drhex.
I've already bought it.
Regards

[Jarek]

ERROR:
   VECTOR_MOD and LEVEL_ATT calibrations fail with 'Reference voltage oot (6.9 ... 12V)

Which reference voltage exactly is it?