EEVblog Electronics Community Forum
Products => Test Equipment => Topic started by: redlght on February 07, 2018, 06:09:04 am
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I contacted US based Advantest they got a hold of their over seas factory and also the company they gave these units to and no one can come up with a service manual or schematic.
My issue is the master 10MHz reference is 260Hz high and that is with the menu course and fine at zero and it will not pass the RBW cal. Does any know which board holds the 10MHz reference and if it is manually adjustable? If not it may need a new xtal. Or any photo of one of these tore down? If i use an external 10MHz reference it cals fine. Thanks for your time
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It's pretty easy to get to. Here's a view from the underside of the machine. CRT is facing to the bottom and the synthesizer deck has been hinged open to the left.
https://photos.app.goo.gl/vUkOOIaIuTJxF9cU2
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Thanks for the photo, mine does not have that 10Mhz ref block , Is that an R3267 with the LCD screen?
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My bad, I posted a photo of a R3371A which has a similar RF deck to the R3265/R3271 but *not* the newer R3267/R3272. On the R3272, which has a much closer design to your device, the 10MHz reference is behind the 3rd converter, underneath the "3rd out" label.
Since removing the RF deck is a PITA you probably want to verify this first. Start at the synthesizer card. There should be 3 or 4 cards accessible after removing a panel on the right hand side (or what would be the right hand side were it sitting in the configuration it is designed to be used in). The synthesizer is the one with ~10 SMB connectors rather than 2 or 3 SMB connectors. Start at the SMB connector nearest to the back of the device and work towards the front, looking for 10MHz with an oscilloscope. IIRC the 10MHz reference should be the 2nd or 3rd you test. You can then trace the cable and will probably find that it does in fact disappear behind the RF deck.
Good luck, let us know how it goes!
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I checked the signal before and it is off by 260Hz coming from under the rf deck on what seems to be a separate board also under the rf deck are maybe 2 boards it is really hard to tell. And yes it is quite intensive to remove but i need to correct that freq offset to able to not use a ext ref. So i guess i have to grin and bare it and get it apart. I was just hoping someone had done this before and had tear down pics, Thanks for your insight
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I have been busy have not yet tore it down, I will update with photos when i do.
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Getting at that 10mhz ref was a bit to much hassle so i sold it to someone that wants to mess with it