GS1100-a voltage out inaccurate

Gamma spectacular, theremino adapters, non-sound card based, etc...
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gianlu383
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GS1100-a voltage out inaccurate

Post by gianlu383 » 15 Sep 2018, 18:42

hi steven,
I just bought the gs-1100 A but I could not make decent spectra.
the spectra did not come because the tension was not correct.
if I put the gs at 9 to get 750v
the spectrum is ok.the voltage I measure it with a high-impedance multimeter, (1gohm) I measure the theremino and it's ok. What I asked was if there is a way to "tune" the tensions with the talking scale.

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gianlu383
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Re: GS1100-a voltage out inaccurate

Post by gianlu383 » 16 Sep 2018, 01:14

thank you regards.

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Sesselmann
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Re: GS1100-a voltage out inaccurate

Post by Sesselmann » 16 Sep 2018, 09:39

Hi and welcome to the forum..

Sorry to hear that you are experiencing issues with the GS-1100A. To answer your question first, no there is no way to adjust the voltage on the GS-1100A model, the circuit uses a string of zener diodes to regulate the voltage, and the 12 way switch simply taps out the voltage between the zeners.

The circuit can only supply a small current, so it is essential to use a high impedance volt meter when testing, but I see you already understand this.

I test the GS-1100A on my work bench with a 1 Gohm, 100:1 divider and the voltages should be accurate to within 10 volts after a few minutes warm up.

It's very uncommon to hear of this problem, in fact I don't think anyone has brought this up before, but I guess it's possible for a diode to fail, or maybe I had a bad day and soldered one diode the wrong way :)

If you are confident there is a problem, I am happy to send you a new replacement board.

PS: We have a rule here on our forum that we use real names (at least first name), so please create a signature in the UCP, so members can address each other by real names.

Thanks.

Steven

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gianlu383
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Re: GS1100-a voltage out inaccurate

Post by gianlu383 » 16 Sep 2018, 19:11

Thanks steven,
For more clarity I am attaching photos of my measurement system.
I did a test with the eberline esp2.
set at 700 vdc. I have a 60 vdc error that I know. measuring the gs1100
set at 7 I have 200 vdc less. add an instrumentation error of 20 vdc.
thank you. regards.
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Sesselmann
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Re: GS1100-a voltage out inaccurate

Post by Sesselmann » 16 Sep 2018, 20:54

Gianluka,

Thanks for images, it looks like we are out by 200V, which is consistent with a faulty or wrong soldered Zener diode. The first three Zeners are 200V each, which is why the GS-1100A srarts at 600V. I made up a new board today, will post it tomorrow.

BTW, as a mad fusioneer, I love your flux capacitor ;)

Steven

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gianlu383
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Re: GS1100-a voltage out inaccurate

Post by gianlu383 » 17 Sep 2018, 00:25

ok, thanks steven,
congratulations for your work and for this beautiful forum.

PS: maybe one day you can make a flux capacitor ..... remember ... 1.21 gigowatt :-)))

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Sesselmann
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Re: GS1100-a voltage out inaccurate

Post by Sesselmann » 17 Sep 2018, 11:05

Gianluka,

Replacement board shipping today, check your PM for tracking number.

My best fusion energy output is around 5x10^6 neutrons/second which works out to around 3 microwatt ;)

Steven

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gianlu383
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Re: GS1100-a voltage out inaccurate

Post by gianlu383 » 17 Sep 2018, 23:10

thank you so much steven.
I'll let you know as soon as it arrives.

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gianlu383
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Re: GS1100-a voltage out inaccurate

Post by gianlu383 » 27 Sep 2018, 04:00

hello steven, today has arrived the new board.working very well!!!.I am very happy.I immediately made a bit of measurements.thanks to your disponability and assistance.
lu 176 calibration source

radio test

all ok. best regards
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Sesselmann
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Re: GS1100-a voltage out inaccurate

Post by Sesselmann » 27 Sep 2018, 11:55

Gianluka,

Great..., pleased to hear that it's working. Looks like the old board had a dead diode, or maybe one upside down diode (my fault :p ).

Great spectra, keep up the good work!

Steven