GS-USB-PRO (V3.2) From Serial #1406 and above.

Gamma spectacular, theremino adapters, non-sound card based, etc...
Post Reply
User avatar
Steven Sesselmann
Posts: 758
Joined: 27 Apr 2015, 11:40
Location: Sydney
Contact:

GS-USB-PRO (V3.2) From Serial #1406 and above.

Post by Steven Sesselmann » 26 Jan 2020, 14:16

This post is probably of limited interest to the group in general, but it serves as a journal or benchmark for my hardware changes. Each time I manufacture a new batch of circuit boards I make a few hardware changes and improvements. I just started using GS-USB-PRO V3.2 and put the board through a series of tests, and it all tested good. So just for the record;

1) C5, C6, C7 & C23 replaced with SMD capacitors of the same value
2) C1, C2, C3, C4, C8, C9, C10, C11 Electrolytic caps replaced with SMD caps of the same value
3) C12 and C13 changed to 30 pF for more reliable USB connection.
4) Three mounting holes added for optional Schmitt trigger conversion (neutron detectors)
5) Power to opamp (pin 5) changed from 3.3V to 5V (slightly improved linearity at top end)

These are very minor changes and no one should notice the difference, except me, as there is a bit less hand soldering.

Steven
v2-1.JPG
GS-USB-PRO (V2.1)
V3-2.JPG
GS-USB-PRO (V3.2)

Conor Whyte
Posts: 92
Joined: 28 Apr 2019, 15:06
Contact:

Re: GS-USB-PRO (V3.2) From Serial #1406 and above.

Post by Conor Whyte » 27 Jan 2020, 07:25

Nice changes. Just thinking, for those people using faster scintillation mediums a TLV320ADC5140 capable of 768Khz sampling might be something to look into? CLK input would be ~36.8Mhz
I like your product and small changes. It keeps evolving :)

User avatar
Steven Sesselmann
Posts: 758
Joined: 27 Apr 2015, 11:40
Location: Sydney
Contact:

Re: GS-USB-PRO (V3.2) From Serial #1406 and above.

Post by Steven Sesselmann » 27 Jan 2020, 08:45

Conor,

Yes, small changes at the time, like natural evolution, I make mistakes and discover improvements :)

I am aware of the faster ADC's, but unless I am mistaken, the chip I use is the only one with built in USB connectivity. Switching to a fast ADC means more digital circuitry and some kind of micro to handle the USB, that will require quite a bit more R&D.

For 99% of users their detectors are the weakest link, not the spectrometer or the sample rate. Only a few specific experiments require faster sampling.

Steven

User avatar
iRad
Posts: 129
Joined: 01 May 2015, 12:27
Location: Stuart, FL USA
Contact:

Re: GS-USB-PRO (V3.2) From Serial #1406 and above.

Post by iRad » 27 Jan 2020, 10:36

Steven - Ever look at any 192KHz/ 32bit single chip solutions from Cmedia? Like the CM6642 for instance...
https://www.cmedia.com.tw/products/USB20_HIGH_SPEED
Cheers, Tom Hall / IRAD INC / Stuart, FL USA
Please check out my eBay Store: http://stores.ebay.com/The-Rad-Lab

User avatar
Steven Sesselmann
Posts: 758
Joined: 27 Apr 2015, 11:40
Location: Sydney
Contact:

Re: GS-USB-PRO (V3.2) From Serial #1406 and above.

Post by Steven Sesselmann » 27 Jan 2020, 16:46

Thanks Tom,

Never come across that chip before, it looks interesting, might be a suitable upgrade. Shall study study the pin out and if suitable get some sample chips to play with. makes it a lot easier if it has the USB functionality built in.

Steven

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest