Author Topic: Fluke 6060A RF Signal Generator Troubleshooting - No Output <250 MHz  (Read 1902 times)

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Offline davefrTopic starter

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I have a older Fluke 6060A RF Signal Generator.  It powers up and completes self test with no errors.  It seems to function just fine at frequencies above 250 MHz.  But the instant I step it down one notch below 250 MHz output drops to zero. Anyone have one with a similar history.  Any suggestions where to begin the troubleshooting process?  TIA.
 

Offline Jay_Diddy_B

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Re: Fluke 6060A RF Signal Generator Troubleshooting - No Output <250 MHz
« Reply #1 on: September 12, 2021, 10:40:50 pm »
Hi,

RF generators like these generate the signals in bands. There are switches that switch between the bands. The symptoms you describe means part of the .1 - 245 MHz signal path is broken.

This is from the manual:




The manual is too big to attach here.

Send me a PM if you can't find the manual.

Regards,
Jay_Diddy_B
« Last Edit: September 12, 2021, 10:42:21 pm by Jay_Diddy_B »
 
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Online TheDefpom

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Re: Fluke 6060A RF Signal Generator Troubleshooting - No Output <250 MHz
« Reply #2 on: September 13, 2021, 03:52:14 am »
I repaired a 6060B about 5 years ago back in my very early youtube days, here is the playlist, it might be helpful as I remember a similar issue.

Cheers Scott

Check out my Electronics Repair, Mailbag, or Review Videos at https://www.youtube.com/TheDefpom
 
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Offline bob91343

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Re: Fluke 6060A RF Signal Generator Troubleshooting - No Output <250 MHz
« Reply #3 on: September 13, 2021, 05:47:39 am »
Looks like a problem with the U201 mixer or associated circuitry.
 
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Offline wn1fju

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Re: Fluke 6060A RF Signal Generator Troubleshooting - No Output <250 MHz
« Reply #4 on: September 13, 2021, 12:15:58 pm »
If I recall, the board layout of the 6060A pretty much followed the block diagram.  Just probe along until you find the culprit.  In my case, I had a problem with one of the amplifiers.  The amplifier used several discrete transistor stages and one of the resistors surrounding the transistors in the amplifier burned up (they were underrated in my opinion and I replaced them with higher wattage versions).
 
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Offline davefrTopic starter

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Re: Fluke 6060A RF Signal Generator Troubleshooting - No Output <250 MHz
« Reply #5 on: September 13, 2021, 01:10:53 pm »
Thanks everyone!! This is a great head start.  It sure looks like something in that portion of the block diagram will be the culprit.  Hope it doesn't turn out to be some proprietary/unobtainium component.
 

Offline davefrTopic starter

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Re: Fluke 6060A RF Signal Generator Troubleshooting - No Output <250 MHz
« Reply #6 on: September 13, 2021, 05:59:18 pm »
If I'm reading this right, HETL toggles the generator from low band to high band. When it toggles to low band, mixer U201 heterodynes the difference between 800-1045 MHz and 800 Mhz to create the frequencies below 245 MHz and that get's routed to the output.

It sounds like the game plan is to confirm good 15 VDC going to Q202, Q204, Q206, Q207 and Q301.  After that check that 800 MHz is being produced at TP5.

My scope max's out at 300 MHz.  Any creative ways to check 800 MHz other then purchasing a high end frequency counter?
 

Offline bob91343

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Re: Fluke 6060A RF Signal Generator Troubleshooting - No Output <250 MHz
« Reply #7 on: September 13, 2021, 06:27:23 pm »
Your scope may still have some usable sensitivity at 800 MHz.  Or you can use the venerable HP 410B.
 

Offline charlyd

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Re: Fluke 6060A RF Signal Generator Troubleshooting - No Output <250 MHz
« Reply #8 on: December 09, 2024, 06:16:30 pm »
Nice topic... i have the same issue with my 6062A.  i didn t do more research yet.  next weekend i ll dive into..
but thanks for the post history. 😉
 


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