EEVblog Electronics Community Forum
Electronics => Repair => Topic started by: enut11 on June 10, 2017, 05:55:02 am
-
Hi
I have just taken delivery of an old Wavetek Model 29 10MHz DDS Function Generator. The eBay listing showed this as a working model and the seller confirmed this when I contacted him. A boot problem has occurred between leaving the USA and arriving in Australia.
The Wavetek seems to boot up and shows the correct boot screen. However, when I try to change the frequency from 10KHz using the rotary knob, it just reboots itself amid random sounds from a relay switching.
A Forum search for this model did not show any hits. I have done a casual internal inspection but no measurements yet except for the Li EEPROM battery which is 3.0v (new Li cell is 3.3v). Nothing else appears to be suspect.
I have downloaded the Operator and Maintenance manuals and currently going through them. I will soon be inspecting the electro caps and doing voltage rail measurements. Any other suggestions welcome.
enut11
-
does it have socketed chips in it ?? simply remove them and re-seat them ???
-
Thanks @coromonadalix. After measuring all DC voltage rails with nothing amiss I set about re-seating all plug-ins. Since then (fingers crossed) things have settled down and I am doing a soak test.
Calibration
I started to look at calibrating the Wavetek. It is a closed-box cal system, all done from the front panel. However, the previous owner password protected the cal menu and the eBay seller cannot help.
I noticed that there is an open 2-pin header behind the Li battery on the PCB. I wonder if this is for resetting the instrument back to factory defaults? Unfortunately the service manual is not helpful, only saying to contact the manufacturer. I am reluctant to short this header out without more info.
Any suggestions?
enut11
-
I believe IIRC that is for resetting the calibration password.
Sam
-
Hi Sam. Thanks for your input. Are you referring to 'LK1 RESET' as per the posted schematic or to something else?
If 'LK1 RESET', is this shorted before or after power up? Will I also lose Cal Constants?
enut11
-
That jumper resets the password for Cal to 0000.
IIRC all you need for the procedure is a accurate DVM. I have attached the latest firmware. If you send me a PM with your email address I will send you the maintenance manual and the full operators guide. Both are too large to attach here.
These generators were made by AIM/Thurlby-Thandar as their model 1010. Fluke and Datron also marketed this generator under their name.
These are really great generators more useful than the Model 39. You can download Waveform Manager Plus from TTI for free to drive it with Windows (it may even work in Linux under Wine). This software allows you to create arbs either mathematically, free hand with a mouse or by downloading from a scope.
https://www.aimtti.com/resources/waveform-manager-plus-v410 (https://www.aimtti.com/resources/waveform-manager-plus-v410)
Sam
W3OHM
-
I am 99 44/100ths percent sure that it does not affect the cal constants as IIRC one of the two that I have I had to reset the password. In any event it is very easy to recal.
Sam