Author Topic: Wavetek 4808 Unstable DC Voltage  (Read 795 times)

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Offline Kenny PowersTopic starter

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Wavetek 4808 Unstable DC Voltage
« on: March 28, 2018, 05:14:41 pm »
Hello,

Posted this in the wrong settion earlier,

I have a 4808 which is exhibiting intermittent misbehavior details below, has anyone else come across this and found a cure? I opened the unit and its spotless inside.

For example, when set for 10VDC, it outputs 10V - but then the voltage (sometimes) slowly drift upwards
to, say, 12.6V.

When this happens:-
- the 1V and 100V ranges are seen to behave similarly
- there is no output on the lower ranges
- the 1000V range seems OK.

The problem can be resolved, at least temporarily, by cycling the power or going up and down through the ranges a couple of times.

(All other functions – ACV, Ohms etc. seem ok)
 

Offline Samogon

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Re: Wavetek 4808 Unstable DC Voltage
« Reply #1 on: March 28, 2018, 09:57:10 pm »
Looks like devider board has issues. But reference is ok
 

Offline Kenny PowersTopic starter

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Re: Wavetek 4808 Unstable DC Voltage
« Reply #2 on: March 29, 2018, 12:07:14 am »
Any idea where this board is located or part number?
 

Offline KhronX

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Re: Wavetek 4808 Unstable DC Voltage
« Reply #3 on: March 29, 2018, 12:19:03 am »
Depending on the age of the unit, there's a chance some of the electrolytic caps might've started to kick the bucket.
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