Got this for cheap....up to x1000 gain, 8 independent, single-ended channels. BNC in/outs.
See below for my ideas... what to use this for...audio-wise.....
Trig Tek Incorporated.
Model 208b
![20230119_184040[1].jpg](https://www.diyaudio.com/community/data/attachments/1042/1042299-1c32db2542e44c36760782b1113dd442.jpg?hash=HDLbJULkTD "20230119_184040[1].jpg")
![20230119_184051[1].jpg](https://www.diyaudio.com/community/data/attachments/1042/1042300-0d0e592c8800ceb31d55a1f1560f5017.jpg?hash=DQ5ZLIgAzr "20230119_184051[1].jpg")
I contacted the new company (Astronics, link) and inquired about obtaining a manual, as I could not find one anywhere.
They said they no longer have those files for their discontinued products of this vintage.
So, I'm still looking for a manual (or it's younger brother, Model 205b).
The unit is pretty straight-forward, though I'd like to know the calibration process. Each board has 4 trimmers.
Also, each board has an empty 8-pin DIP socket, which I believe is for optional filters (Hi, Low, Bandpass, whatever.....I'm not positive.)
I may have to re-engineer the circuit.
![20230119_183546[1].jpg](https://www.diyaudio.com/community/data/attachments/1042/1042305-06ae22a6f08124215fae7868bf653023.jpg?hash=Bq4ipvCBJC "20230119_183546[1].jpg")
![20230119_183601[1].jpg](https://www.diyaudio.com/community/data/attachments/1042/1042306-cfb443c43b76984dfd143f4b4fa64f48.jpg?hash=z7RDxDt2mE "20230119_183601[1].jpg")
![20230119_183609[1].jpg](https://www.diyaudio.com/community/data/attachments/1042/1042307-41853fc9a7ac7ed988b5a46b9719c638.jpg?hash=QYU_yaesft "20230119_183609[1].jpg")
The 16 pin socket connects a ribbon cable to each switch. The 8 pin socket might be for optional filters (??)
All the Lorlin 12 pos. switches were hardly working (no signal).
I opened one up, and found the contacts had a covering of hardened goo. I tested all my solvents, and the only one that worked was Naptha.
There are vent holes in the switch body, so I flushed each switch with Naptha, then blew them out with compressed air. I repeated with Isopropyl Alcohol, and finally a couple drops of DeOxit Gold.....spinning the contacts a lot.
Switches fixed.
Passes clean signals.
Main chip....
PGA207ua ..............5-MHz, 100-pA bias current, FET input programmable gain (g=1,2,5,10) instrumentation amplifier (link)
I assume this was used to amplify load-cells, strain gauges, vibration monitors, or accelerometers.....??
WHAT COULD I USE THIS FOR ??
I'm not sure......mic preamps ? .....piezo-acoustics ? test/measurements ? Making experimental/unusual sounds from tiny signals ?
(I make music and sounds with my modular synth, so.......)
See below for my ideas... what to use this for...audio-wise.....
Trig Tek Incorporated.
Model 208b
I contacted the new company (Astronics, link) and inquired about obtaining a manual, as I could not find one anywhere.
They said they no longer have those files for their discontinued products of this vintage.
So, I'm still looking for a manual (or it's younger brother, Model 205b).
The unit is pretty straight-forward, though I'd like to know the calibration process. Each board has 4 trimmers.
Also, each board has an empty 8-pin DIP socket, which I believe is for optional filters (Hi, Low, Bandpass, whatever.....I'm not positive.)
I may have to re-engineer the circuit.
The 16 pin socket connects a ribbon cable to each switch. The 8 pin socket might be for optional filters (??)
All the Lorlin 12 pos. switches were hardly working (no signal).
I opened one up, and found the contacts had a covering of hardened goo. I tested all my solvents, and the only one that worked was Naptha.
There are vent holes in the switch body, so I flushed each switch with Naptha, then blew them out with compressed air. I repeated with Isopropyl Alcohol, and finally a couple drops of DeOxit Gold.....spinning the contacts a lot.
Switches fixed.
Passes clean signals.
Main chip....
PGA207ua ..............5-MHz, 100-pA bias current, FET input programmable gain (g=1,2,5,10) instrumentation amplifier (link)
I assume this was used to amplify load-cells, strain gauges, vibration monitors, or accelerometers.....??
WHAT COULD I USE THIS FOR ??
I'm not sure......mic preamps ? .....piezo-acoustics ? test/measurements ? Making experimental/unusual sounds from tiny signals ?
(I make music and sounds with my modular synth, so.......)
Check the slew rate, 741 / 358 and other op amps were intended for such use, stability is valued in that field, and shielding from transients.
In audio, that can be a disadvantage.
Best thing is refurbish it, and use as intended, or sell it off as a working unit, finding buyers is something I cannot tell you about.
In audio, that can be a disadvantage.
Best thing is refurbish it, and use as intended, or sell it off as a working unit, finding buyers is something I cannot tell you about.
Its more likely targeted at biotech. The high gain diff amps can be used to measure skin potentials etc. Have you measured its performance? If the noise is low enough it could be a good 8 ch microphone preamp.
"INSRTUMENTATION" ?? Really??
BNC inputs are generally not differential? I see this PGA chip is, and that was used as mic-amps. But some labor to drill-out and fit for XLRs.
Tantalum rail-caps for future "fun".
Great box if you can re-jack it.
