Help Wideband PLO (Phase-Locked Oscillator) display model BHE BSVB23 DOCUMENTAION/Datasheet

Hi,

How are you measuring it, and are you sure your measurement setup and tools can accurately measure the output? Diagram or photo of your test setup showing all connections would be good.

Secondly, there's very high chance the synthesizer doesn't have the circuitry for a flat output anyway. You could just try to follow the traces from the VCOs (visible in your photo as metal Minicircuits cans) and see what circuitry got used for amplifying and level control (if any).

If there's highly unexpected output difference then the output amplifiers could be faulty. Your photo has chopped that important part off, you can just about see the amplifier at the bottom, for one of the VCOs. But again, I don't expect flat output at all.

If the amplifier on the left side of the photo is faulty, then you can easily replace it, it is part ERA-5

https://www.minicircuits.com/pdfs/ERA-5+.pdf

Hi,

First thank you very much for your reply,

Below is my setup on how I test my WideBand . Just a power supply @ 15Vdc and the terminal output connected  to the signal analyzer, and Im looking at the magnitude phase peak output (in dBm) @2Ghz:

- First Im using a working WIDE BAND  PLO with a phase magnitude output giving approximaetely 10 DBm @ 2Ghz (See photo below) it is the manufacturer specifications :

@15V

- Then I check the faulty  Wide Band  : @ 2 Ghz I get -3.6 dBm. There are other peaks at other frequencies,  so you can see on the pcture. So it seems to work at least partially but I have an issue on th magnitude..



I opened the back cover of the faulty Wide Band and I checked step by step as pictured below the peak output magnitude (dBm)  to try how the signal evolve through the amplifier stages :

amplifier E5 close to the terminal output:


measute at point 1 (amplifier input)  magnitude peak  -14 dBm

measure at point 2 (amplifier output) magnitude peak 2.2dBm +2 dBm

measure at point 3 after the capacitor magnitude peak 2.2dBm

measure at point 4 :  magnitude peak -18 dBm

and then checked the  the peak output magnitude on the other amplifier



measure at point 1.1 (amplifier input) :  magnitude peak -11 dBm

measure at point 2.2 :  magnitude peak -24 dBm

and measure at point 3.3 after the capacitor :  magnitude peak -28 dBm

It looks like the magnitude of the second amplifier is always negative . So is it coming from here ?

I have to mention that the first time I opened the Wide band, I had to rebuild the voltage divider bridge close to the output  teminal  (I wasn't sure avout the contact output teminal with the resistor bridge when I unmounted it) . I wasnt sure about the middle resistor value between the 820ohm resistors (seems to be GND- 820 ohms - teminal output connection - 560ohms -  820 ohms -GND)  see below :

Thanks in advance for any of your suggestions / advices.