My E4407B is giving 4 dB relative loss from 3 GHz to 26.5 GHz compared to 50 MHz. It appears that the loss of the RYTHM mixer A8A6 assembly has increased from 12dB to 16 dB. Why is this? Is a schematic available? Are the mixer diodes failing? Others on the web have the same issue.
Hello WizardRF,
It is difficult to find the root cause from this end however maybe I can provide some resources to help you out.
Here is a link to the service guide which provides:
Description of the RYTHM mixer: Pg. 101
Block Diagram: Pg. 135
Part Numbers of the RYTHM mixer: Pg. 211
In addition, here is a link to the calibration guide although I assume you are already aware of this.
If you want us to look at it, you could also try sending it in for repair and calibration with this link.
The last link also provides information about finding certain parts and manuals.
Hi,
Thanks for the reply. I have had the RYTHM mixer assembly repaired, and all is well. I will probably send the unit to Keysight for re-adjustment of the calibration data, but the frequency response is not too far off now.
Regards,
Richard Laver
Waterbeach Electronics Ltd.
Hello WizardRF,
It is difficult to find the root cause from this end however maybe I can provide some resources to help you out.
Here is a link to the service guide which provides:
Description of the RYTHM mixer: Pg. 101
Block Diagram: Pg. 135
Part Numbers of the RYTHM mixer: Pg. 211
In addition, here is a link to the calibration guide although I assume you are already aware of this.
If you want us to look at it, you could also try sending it in for repair and calibration with this link.
The last link also provides information about finding certain parts and manuals.