hope I put , then , 7812 ....... or you're going to be in trouble
take care of D7 value on channel pcbs
(enough) for that at a time
7812, yes you smart : ),for D7... i´ll look it up tomorrow, i think i activated brain and checked it and its ok...
yup , I've put these pads there exactly for measurements purpose......
if you're sure in your work (parts placement etc.) and properly set trimpots in buffer (lower one-CCS- set to max ) just bang it ....... set Good Gemini voltages (+/-12Vdc) , and then proceed to setting output buffers
of course - connect Turtle to channel pcbs only when you already set buffer DC output offset
edit: I personally prefer straight buffer schm to Borbely WCF iteration ; that way IP is in invisible mode , just as I like it
if you're sure in your work (parts placement etc.) and properly set trimpots in buffer (lower one-CCS- set to max ) just bang it ....... set Good Gemini voltages (+/-12Vdc) , and then proceed to setting output buffers
of course - connect Turtle to channel pcbs only when you already set buffer DC output offset
edit: I personally prefer straight buffer schm to Borbely WCF iteration ; that way IP is in invisible mode , just as I like it
that was superconvenient : )
shunt regs were about 12,5 initially, easy to trim.
initial bias was about 17 mA, easy to trim to 21mV across R34 also. I was at least clever enough to leave some hight on R34 for easy measuring.
Offset also easy to trim!
few hours finishing ...: )
best
stefan
shunt regs were about 12,5 initially, easy to trim.
initial bias was about 17 mA, easy to trim to 21mV across R34 also. I was at least clever enough to leave some hight on R34 for easy measuring.
Offset also easy to trim!
few hours finishing ...: )
best
stefan
: ), yah, you know me. Porn a bit later,
a little already asked question again (sorry for that, couldn´t find it with search).
I asked for using a stereo plug (for i-pods etc), and how to manage (separate) the common ground on those plugs.
Your recommendation was to put a resistor in gnd to one channel? About 100 Ohms?
tnx!
st
a little already asked question again (sorry for that, couldn´t find it with search).
I asked for using a stereo plug (for i-pods etc), and how to manage (separate) the common ground on those plugs.
Your recommendation was to put a resistor in gnd to one channel? About 100 Ohms?
tnx!
st
10-15-22
as low as you can , without making huuuuuummmmm
though , first try with regular cable , this drek is floating anyway ( no connection with safety gnd) , so most probably no gnd loop
anyway , there are ntcs in IP , so ground loop is hardly possible, whatever you connect to input
as low as you can , without making huuuuuummmmm
though , first try with regular cable , this drek is floating anyway ( no connection with safety gnd) , so most probably no gnd loop
anyway , there are ntcs in IP , so ground loop is hardly possible, whatever you connect to input
Last edited:
damned, i have appointment now and to leave.
it sings : )
i have just one set RCA cables (from COmputer) pluged in. When i dial another source (so empty RCA on Preamp) i have a quite a loud distorted signal (on all other souces/emty RCAs). turning the pot does not change Level of distorted signal. When i pull out one RCA plug there is just undistorted signal on the chosen source...and complete silence on the other sources..
shure it is some signature stupidness i made : )
Will have a fresh eye tomorrow.
Ah, it was a bit fusehungry in the beginning, but now seems to be ok...
more tomorow
it sings : )
i have just one set RCA cables (from COmputer) pluged in. When i dial another source (so empty RCA on Preamp) i have a quite a loud distorted signal (on all other souces/emty RCAs). turning the pot does not change Level of distorted signal. When i pull out one RCA plug there is just undistorted signal on the chosen source...and complete silence on the other sources..
shure it is some signature stupidness i made : )
Will have a fresh eye tomorrow.
Ah, it was a bit fusehungry in the beginning, but now seems to be ok...
more tomorow
post some pics and I'll help ; you certainly swapped gnd and hot somewhere
as I made it - all unused inputs are hard grounded , only used input is open and connected to buffer input
fuse-hungry - Donut I sent you is 30VA , so with 230Vac mains , it calls for 120mA-160mA ...... both F and T will do ...... better F
as I made it - all unused inputs are hard grounded , only used input is open and connected to buffer input
fuse-hungry - Donut I sent you is 30VA , so with 230Vac mains , it calls for 120mA-160mA ...... both F and T will do ...... better F
dear ZM, had some time to comb the signal hairlike cables and crosstalk is gone : )
Also fuse is staying. Maybe it was the caps conditioning or so.
Crazynice preamp. A real joy to make. Not just convenientwise (flatcables), also conceptwise, with good buffer, thank god presoldered jfets : ), a more or less custom made autoformer, the whole relaythingie and last not least, thank god no remote conrol
Also fuse is staying. Maybe it was the caps conditioning or so.
Crazynice preamp. A real joy to make. Not just convenientwise (flatcables), also conceptwise, with good buffer, thank god presoldered jfets : ), a more or less custom made autoformer, the whole relaythingie and last not least, thank god no remote conrol
you made some reallly big ookup with cables , if you had xtalk
as I said - inactive inputs are hard grounded ......
anyway , I like that you like it ...... and how you like sound (or lack of same ) of it?
porn?
(if you post some pics , maybe I can see is there something to optimize .......)
as I said - inactive inputs are hard grounded ......
anyway , I like that you like it ...... and how you like sound (or lack of same ) of it?
porn?
(if you post some pics , maybe I can see is there something to optimize .......)
a piccie, but its also in the gallery
It´s singing just for few minutes, but soundwise great depth, dynamics, all there
: )
nice ......... even if just one pic
Fugly!
i guess it´s funny having the pics here too,
you deserved it : )
you deserved it : )
Attachments
-
IMG_7115.jpg250.4 KB · Views: 198
-
IMG_7113.jpg259.9 KB · Views: 189
-
IMG_7112.jpg279.4 KB · Views: 252
-
IMG_7110.jpg388.1 KB · Views: 243
-
IMG_7109.jpg267 KB · Views: 233
-
IMG_7108.jpg370.1 KB · Views: 237
-
IMG_7106.jpg342.9 KB · Views: 415
-
IMG_7105.jpg369 KB · Views: 436
-
IMG_7103.jpg277.7 KB · Views: 446
-
IMG_7116.jpg235.3 KB · Views: 220
- Home
- Amplifiers
- Pass Labs
- Iron Pumpkin(s) and other smaller vegetable animals, Tips 'n' Tricks thread