View Full Version : Teddyreg build/ attempt from a 140.


The Captain
21-11-07, 04:56 PM
Hi, Ive a plan to power 322MM boards in a 32.5 with two Teddyregs mounted nearby: to keep it simple I'll try powering both Tregs from the unhooked 24v in my 140. A few Qs before I start building if anyone can help..

1) Does anyone know which resistor on the 140 PS board I need to change to get 32v? ie its 24v now/ 32v needed.
2) Teddyregs: do the tants on the Teddyreg all need to be 25v minimum? (I can only find 10v or 16v 20-33uf tants).
3) Schematic: is top LHS= + in/ top RHS= +out.. bttm LHS= 0v in/ bttm RHS= 0v out? so that:
4) all tants + legs should face up twds this top rail on schemo, - legs face downwards?
5) Any opinions as to where I can best take two 0vs needed (one into each Treg) & whether terminating them at the preamp star is best out from Tregs?

Thanks, Captain.

teddy_pardo
21-11-07, 09:35 PM
You can find the tantalum capacitors on ebay (http://cgi.ebay.com/25pcs-Dipped-Tantalum-Capacitors-33uf-35v-capacitor_W0QQitemZ200171317419QQihZ010QQcategoryZ 40114QQrdZ1QQssPageNameZWD1VQQcmdZViewItem). Don't use anything below 35V

Naim usually use three resistors for the LM317, two of them are in series and are in fact one. increasing one of them will increase the output voltage.

yairf
21-11-07, 11:54 PM
Why use the 24v from the 140 when you have 34V with high capacity? use it with Teddy-Reg and you get a perfectly clean 24V supply. That's what I did, works a treat!

The Captain
22-11-07, 05:12 AM
Why use the 24v from the 140 when you have 34V with high capacity? use it with Teddy-Reg and you get a perfectly clean 24V supply. That's what I did, works a treat!

Hi Yairf- Im not exactly sure what '34v with high capacity' means? maybe its exactly what I have in mind, ie change the lm317 resistors to send 33v ish instead of 24v.. but do you mean you took raw dc from the 3,300uf nap 140 cap unhooking all the lm317 circuit?

Thanks for the link Teddy- I dont suppose silmic 47uf/ 50vs could be used instead of the 20-33uf tants, or any other substitutes in your opinion?

yairf
22-11-07, 06:30 AM
I'm refering to the main caps (for the NAPA board), where you have +/- 34V with plenty of capacity (I have increased capacity to 4 x 15,000uF...)

The Captain
22-11-07, 07:12 AM
Understood, thanks Yairf. What's your opinion on taking raw dc from the single 3,300uf nap PS capacitor for two Tedyregs> two 322s?

& do you have any pics of your mods? thanks Capt

yairf
24-11-07, 04:12 AM
Hi Captain
The big advantage of using the power-amp rails, is that you have plenty of voltage to drop-out. The power-amp will create some ripple when pushed to high levels, but that's when the TeddyRegs step in and do their job.
As for the secondary PS in the 140, I had to remove it to make space for the 15,000uF caps - these are now stitch-wired directly to the rectifiers and NAPA boards...
It's a lot of work but definitely worth it!
A friend gave a listen to the 62-140 and immediately took custody of both, connecting them to a pair of Harbeth Super-HL5 (what a gem!) so I'm unable to take pics right now...
Cheers
Yair

The Captain
26-11-07, 01:38 PM
Ok Yairf, you're diy on this has me thinking as I had increased my 140 caps to four 10,000ufs ..

so is your idea effectively taking a feed directly off one of the main (positive) cap terminals via the old 24v pin on the rear din connector, into Teddyreg's in your 62?
did you then take a feed from the negative terminal for/ into the Teddyreg's ground, coupling this with the signals ground on the rear din..

or have you made a new, perhaps seperate socket?

yairf
01-12-07, 06:04 AM
Hi Captain
Sorry for the late reply, just landed from another US tour...
Basically, I used the two positive rails of the 140 main caps into the 62, with a common ground (thats goes straight into the 62 star-ground). I used the DIN connectors to do this, while the signal is now routed separately via RCA connectors.
Hope this helps
Yair