sontec 1 RU build thread

If I remember it right the five-pin version is the 'Q' Pot for the low frequency band - will be back home in a couple of hours and can double check.

hth, christoph

Hi, pot with 5 pins is for low band, it has a switch
which changes beetween shelve/bell at ccw pos.

Igor, could you explain the extra cap (unspecified value-optional?) for CLF2'?

Thanks,
Paul

CLF2' is a second placement option for CLF2, if you are using really oversized caps for example. So either place the 4u7 in the slot for CLF2 OR CLF2'

htht, christoph

Ted, I used a ferrite bead for the 0 ohm resistor marked FB. Not sure if this was what Igor intended but it all seems to work. I expect a jumper would be fine too.

[quote author="bearblock"]Ted, I used a ferrite bead for the 0 ohm resistor marked FB. Not sure if this was what Igor intended but it all seems to work. I expect a jumper would be fine too.[/quote]

Interesting... I wondered what "FB" meant because I didn't see a Ferrite Bead in the parts list.

Igor, could you comment on this one.

Oh gosh, I made a terrible mistake, I just broke a dual 100k pot when I tried to shorten the shaft a bit :? - Igor do you still have some pots available, or is anyone else going to order pots in the near future?

Thanks!
Christoph

Yap. I have some 100k dual pots and some 5k's, no 50k lin left.

Just to let you know, i finished my sontec! (will post pics later)
It worked at first power on (ok... i had 1 red and 1 orange led for bypass, damn bright leds) and it sounds great and is dead silent.

Tip:
When you have the purusha case don't solder the switches to the board yet!
wait untill the board is mounted to the panel and then solder the switch, otherwise the switch will be to low on the board and won't reach the hole in the panel and you have to desolder it. (i had to and it's not real easy to do)
Best thing to do is first mount the top board and then the lower board otherwise sodering the switch can be a bit hard because of the space between the top and bottom board..

For the rest...

Big respect for Igor for this project!! :sam: :sam: :sam: :sam: :thumb:

ip:
When you have the purusha case don't solder the switches to the board yet!
wait untill the board is mounted to the panel and then solder the switch, otherwise the switch will be to low on the board and won't reach the hole in the panel and you have to desolder it. (i had to and it's not real easy to do)

Click to expand...

UPS, I just soldered all my toggles on the boards :shock:

[quote author="Purusha"]

ip:
When you have the purusha case don't solder the switches to the board yet!
wait untill the board is mounted to the panel and then solder the switch, otherwise the switch will be to low on the board and won't reach the hole in the panel and you have to desolder it. (i had to and it's not real easy to do)

Click to expand...

UPS, I just soldered all my toggles on the boards :shock:[/quote]

it will fit but it's just a bit harder because you have to desolder the 'groundpins' near the screws.
So... best is to put it on board, fit the board to the panel and then solder it.

Actually they can be soldered in before mounting them but the legs should not come through on the bottom side, than they will be 100% in the right hight.

I guess I will need to buy a special desoldering wire to solve this problem... :grin:

[quote author="Purusha"]Actually they can be soldered in before mounting them but the legs should not come through on the bottom side, than they will be 100% in the right hight.

I guess I will need to buy a special desoldering wire to solve this problem... :grin:[/quote]

True.. but it's hard to 'guess' how high to solder 'm on board but it can be done.
I think it's best to leave the montage/ground pins unsoldered since you have some room then for ABB (Adjust By Bending) technique.
I used quite a simple desoldering pump and a little screwdriver to lift the switch bit by bit.
The second switch i soldered after the board was mounted.

Wired up my first channel and got smoke from the 22R resistors, it seems the PSU markings on the filter board have + and - reversed. Once I traced through the schematic and hooked it up correctly all is fine.

Great EQ! Amazing level of precision.

Now does anyone have a faceplate layout so I can take it off the cardboard?

I'm about to order the Elma knobs from Farnell.

The shafts on Igor's pots are 1/8" 3.15mm

Farnell have 3mm & 4mm knobs. I'd imagine the 4mm would be too slack and the 3mm would just about fit.

Correct or am I way off?

Farnell should have 3.15mm version, IIRC it is just labelled
in inch, not mm...

Damn... I just checked & I ordered 3mm

They do NOT fit!!!

Great... over $100 for knobs & I get the wrong ones.
Time for careful drilling... wish me luck.

I thought for sure they'd fit.
Why the hell are there 3mm & 3.15 mm anyways?
Is the 3.15mm = to 1/4 in maybe?

3.15mm =1/8"

6mm is not 1/4
6.35mm = 1/4"

the 1/4" collets will clamp down on 6mm no problem, but it's rather tuff to get 6mm collets onto a 1/4" shaft. It's mostly brand specific.

I also tried drilling out some and lets just say, I bought the knobs again and will use them for something else someday.

Mouser sells some nice ReAnn knobs in 1/8" and the price is good on large quanitys.

Damn... I just checked & I ordered 3mm

They do NOT fit!!!

Great... over $100 for knobs & I get the wrong ones.
Time for careful drilling... wish me luck.

Click to expand...

Ahemmm.... I had same prob with 6.3mm Grayhill switches
and Elma 6mm knobs, used friend's Proxxon lathe, solved ...
Anyway, if you don't have small lathe, try to fit collet into drill chunk,
but leave 2/3 outside of chunk - not to press the collet much,
otherwise hole will be too big.
With some care, should work.
Good luck :sam: :guinness:

One channel is up and running! Now I just have to wait for Igor's replacement pot I broke and Another ad706 which is backordered...

regards,
christoph