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Eico 902 audio analyzer manual & ?

spaceman

Nov 5, 2016
67
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Nov 5, 2016
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Does anybody have a user manual & perhaps schematic of Eico 902 ?
Also, can this equipment be used as a tone generator like the phone company uses ?
Thanks for any help
 

73's de Edd

Aug 21, 2015
3,613
Joined
Aug 21, 2015
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3,613
Yah . . . . . ive dun been gottink its.


Click on this hot link below . . . . .and then run like hell . . . .since we dont know EXACTLY how BIG that PDF ended up being !

http://bama.edebris.com/download/eico/902/Eico 902.pdf

After your 15 second wait . . . . . .or muuuuuuuuch longer . . . . .for other mere mortals on dial -up.
The parts list and schematic . . . . will mystically and magically . . .appear on its pages 22 and 26 respectively.


As per the use of it with . . .DTMF fequencies . . .I assume.
Eye that frontal frequency dial, but also know that it mechanically couples into a Wien bridge oscillator.
Also note the dials extreme range limits encompassing ~270 degrees of coverage, would suggest of a potentiometer being used.
But, it is actually using an air variable capacitor in conjunction with parallel resistance to acquire its RC time constant aspect.
Its real savior, on its adjustment aspect, is there being a 6:1 vernier drive inserted between the air variable cap shaft and the adjustment knob.
BUT I truly do think that you will
additionally need to have a freq counter sampling its output to confim its true frequency, when adjusting into a specific DTMF frequency.
You will then just have to watch it for a while, to evaluate how well it holds that frequency for time.

HEY ! ya wanna see the
OLD EICO world headquarters, near NOO YAWK CITEE ?
( TOTO . . . .we ' re not in Kansas anymore ! )

ITS VISUAL REFERENCE:

https://www.google.com/maps/@40.653...qtTWC8Xhbtz7Tv7Kw!2e0!7i13312!8i6656?hl=en-US

Now, they even have solar panels on the roof, and even a very slight bit of theft access deterrence by the peripheral rolled coils of barbed concertina wire surrounds.




73s de Edd
 
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spaceman

Nov 5, 2016
67
Joined
Nov 5, 2016
Messages
67
Edd,
Thanks for the links. I searched the world wide web and only found the pay for information sites which I found as an opportunist endeavor to make money. Once the manuals are over a predetermined time ( say three decades I don't find it ethical to charge for manuals ) What you have posted is of much help to me. I have paid for manuals in the past but I find it makes me feel I cheapened myself.
 
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