MJLorton Solar Power and Electronic Measurement Equipment Forum
Older Technology => Older Technology => Topic started by: Mr Eastwood on April 12, 2019, 07:49:42 AM
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Another Ebay low cost ex-mod purchase to add to the collection; not too much to say other the unit looks good inside, no sign of any previous battery leaks. Very nice item, I look forward to playing around with it on the bench.
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Link to a similar unit https://www.vintage-radio.net/forum/showthread.php?t=126780 (https://www.vintage-radio.net/forum/showthread.php?t=126780)
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Very nice looking unit.
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That is mean! >:(
Somehow it would be interesting to me, what the connected DMM shows... :'(
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That is mean! >:( Somehow it would be interesting to me, what the connected DMM shows... :'(
ProBang, I know that was really mean of me, it was wrong wasn't it! :) SO to try make it up to you I have posted some readings;
the dial settings were set at: 4000 on .9999, 9.999 and 99.99 mA ranges respectively matching the images (left to right) or (top to bottom)
the meters used were: idm 305 (1), idm 305 (2), idm 305 (3) and solartron 7150 (1) and solartron 7150 (2)
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Hello!
Thank you for your efforts. It seems, the 505 DC current source is still pretty well in spec. :)
(Maybe a little on the low side, but that could easily caused by the resistance of the test leads and the current shunts. The tolerances of the DMMīs are added anyways.)
So I have to say: I am really very impressed from this device. :o
When was the current source built? My guess would be: Pretty much 40 years ago.
And works still fine...
I donīt expect such a long lifetime from the items, nowadays produced.
BTW: Regarding the readings from your second Solartron 7150: 0.29 mA, 3.88 mA.
Is there sadly a problem in the lower current range? ???
Greetings
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Hi,
"When was the current source built? My guess would be: Pretty much 40 years ago."
Quite possibly, they used the same case design I think for a good few years.
"BTW: Regarding the readings from your second Solartron 7150: 0.29 mA, 3.88 mA.
Is there sadly a problem in the lower current range? "
VERY good point! looking at the service manual there is only 1 range for current and that is 2A; so a big jump like that looked quite odd; so i left both meters on for about 5 hrs; then re-did the readings for #1 and #2; but this time both meters were NULL'd and then i switched on the FILTER.
Basically much better readings.
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Happy to see the second unit works fine, too! :)