Wavetek 9100 - Measurement Failure in Oscilloscope Section. Need Help & Advice.

[izmirli]

hi to everybody.
it is first time, i am writing something to the elsmar forum...i hope to find some solution for my problem about my wavetek 9100.

in aux section. i try to calibrate any oscilascope. however, i cant measure frequencies over 11.2Mhz. there is a problem after i set the output to oscilascope over 11.2 Mhz to maximum value. there is always a noise ..

and, i try to self-test. i came face to face with below messages:

results of FULL TEST...: 2 fails.
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1. Test Number: S03.002

Meas.Value =+12.180057
Upper Lim.Value =+5.875000
Lower Lim.Value=+0.625000
Measured A = +12.180964
Measured B =+12.179151
Description: HF sine VCO control range Lo via V tune.
____________
2. Test Number: S04.003

Meas.Value= - 4.211193
Upper Lim.Value = - 0.150000
Lower Lim.Value = - 2.250000
Measured A = - 4.211193
Measured B = - 4.211193
DEscription: Control volts pin diode max via TT401



______________
Looking for some help. is there anybody who knows something about it?

Thanks..
See u

[harry]

Welcome Izmirli,

We are sorry that you had to post a second time - the first was buried somewhere because it piggy rides on another thread.

Could anybody provide an answer to our new friend?

[Jerry Eldred]

Sounds possibly like your 9100 has a problem. I am not familiar with the test results you entered. However, it sounds like the 9100 attempted to output a voltage level and in its self test was not able to read an acceptable amplitude.

I would suggest you set your oscilloscope to 100 mV/Div, and the timebase as needed to measure 600 mV peak to peak. Then set the 9100 output to 10 MHz and 600 mV peak to peak.

Then measure it on the oscilloscope to be sure the oscilloscope reads somewhere close. If the oscilloscope reads either twice the value or half the value, be sure both are set up for the same input/output impedances (either 1 Megohm or 50 Ohms).

If you can get a successful reading at 10 MHz, then you know your 9100 and the oscilloscope are both working at that point.

Now, once you have that part working, leave everything set up, connected and working.

Then without disconnecting, without turning the signal off, change the output frequency on the 9100 to 15 MHz. You should still see an approximate 600 mV peak to peak on the oscilloscope. If it has become noise, and there is no reasonable signal displayed on the oscilloscope, it appears your 9100 may be broken and will need to be sent in for repair.

One further step you can take is to slowly increase the frequency from 10 MHz upward and see if there is a specific frequency where the output drops off sharply or almost sharply or disappears. When you send it in for repair, be sure to tell them at what exact frequency the signal disappears.

I am assuming also that you are certain your oscilloscope is working properly. If you have some other signal source available (even if it is not very accurate), apply approximately 600 mV peak to peak at a frequency higher than 11.2 MHz and verify your oscilloscope is working. If all the above is true, you need to have your 9100 repaired.

[izmirli]

Elsmar Forum... Harry and Jerry, thanks so much for ur help...

Yeah.. ur last sentence is(unfortunately) true. I need to have my 9100 repaired..
What is nice is; I had many new experiences about Wavetek9100. If someone needs help, just post a message to me, i will try to help u...

bye. and again. thanks.. have a nice life...

izmirli