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Old 31st October 2012, 01:40 AM   #8401
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I got 'lucky'...
...measured my RIAA's today...
...and got a bunch at 47.1/2n & a bunch at 15.4/6n...
...ordered the interstage from the 'old' schematic, by mistake ( dahggg ! )...
...oh well...is 100n NOT 47n...
...should be OK I guess ??

Cheers

Si.
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Old 31st October 2012, 01:55 AM   #8402
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Saw a funny listing on eBay...
it said :-

Ex-Soviet Military guitar-tone capacitors, for THAT 'Woman' tone.

Strange; I didn't think the USSR Army normaly issued any Epiphone Casino's !

Si.
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Old 31st October 2012, 02:05 AM   #8403
Salas is offline Salas  Greece
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Quote:
Originally Posted by The Space Egg Corp View Post
I got 'lucky'...
...measured my RIAA's today...
...and got a bunch at 47.1/2n & a bunch at 15.4/6n...
...ordered the interstage from the 'old' schematic, by mistake ( dahggg ! )...
...oh well...is 100n NOT 47n...
...should be OK I guess ??

Cheers

Si.
What old schematic, and which one you got in mind to do?
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Old 31st October 2012, 08:17 AM   #8404
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sorry for bumping in this thread with my question but I downloaded the schematic of the RIAA stage and seems to me very tempting to try out;
however, I would also like to try it with my R2R tape deck as a play preamp and since I heard that the RIAA filter stage doesn't differ too much from the NAB filter stage used for 19cm/s tapes, I wonder if someone would know how to change the filter values of the RIAA equalization so that I'll be able to use it as a repro preamp also using NAB equalization standard?

Thanks
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Old 31st October 2012, 10:08 AM   #8405
atupi is offline atupi  Romania
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What would better for interstage cap: FT-1 0.022uf 2 pcs paraleled or a single FT-3 0.1uf ?
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Old 31st October 2012, 10:39 AM   #8406
RCruz is offline RCruz  Switzerland
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Quote:
Originally Posted by atupi View Post
What would better for interstage cap: FT-1 0.022uf 2 pcs paraleled or a single FT-3 0.1uf ?
I would use a single 0.1 FT-3
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Old 31st October 2012, 10:39 AM   #8407
RCruz is offline RCruz  Switzerland
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How much VDC from 1K4's right side to capacitor and ground?
23.8V
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Old 31st October 2012, 12:04 PM   #8408
Salas is offline Salas  Greece
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If its about 10.5V across the lower buffer JFET, make it 1.8K so to drop about equal across the upper one. Not that is a real problem, but more elegant having the same dissipation.
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Old 31st October 2012, 12:07 PM   #8409
Salas is offline Salas  Greece
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Quote:
Originally Posted by atupi View Post
What would better for interstage cap: FT-1 0.022uf 2 pcs paraleled or a single FT-3 0.1uf ?
Single cap is more coherent, but if you have big bass reflex speakers and a bit light turntable maybe the lower value can cut more unwanted feedback energy. Evaluate.
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Old 31st October 2012, 12:09 PM   #8410
Salas is offline Salas  Greece
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Quote:
Originally Posted by luxury54 View Post
sorry for bumping in this thread with my question but I downloaded the schematic of the RIAA stage and seems to me very tempting to try out;
however, I would also like to try it with my R2R tape deck as a play preamp and since I heard that the RIAA filter stage doesn't differ too much from the NAB filter stage used for 19cm/s tapes, I wonder if someone would know how to change the filter values of the RIAA equalization so that I'll be able to use it as a repro preamp also using NAB equalization standard?

Thanks
Preamp for reel-to-reel
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