MOTM

Hi,

this is for all who have asked about the status of my Frequency Shifter 
project:

I've just made a major update here:
http://www.jhaible.heim.at/fs1a/fs1a.html

I plan to release this after the Krautrock Phaser PCBs are all sent out.

Right now, I want to find out how many of you are still interested in the 
Frequency Shifter project, now that you see how complex it is.
:)
It'll be my most difficult project so far. Take a look at the schematics, 
and if this doesn't frighten you away, please get back to me. (I certainly 
don't want to sell a lot of boards that will be thrown away unused or 
half-built, or built and not adjusted.)
Pricing will be like my previous PCBs, only that you need *two* PCBs for 
each frequency shifter; that's 54 EUR + shipping.

If you're still interested, please send me a mail - I want to find out if 
I'd get enough orders to get both of these PCBs made in quantities without 
committing commercial suicide. (It will take a couple of months before these 
boards will be ready for shipping, but I need pre-orders now.)

If still interested, please send me a mail in the following form (fill in 
the number or text in [] brackets):

=================================================================================

Email subjet line:  "FS1A PCB order [n] sets of boards"

=================================================================================

Email text:

I'm ordering [n] sets of 2 PCBs for the JH FS-1A Frequency Shifter project 
for EUR 54.00 per set of boards,
plus EUR 8.00 for shipping and handling per order.

This is a binding pre-order that allows you to have a PCB manufacturing run 
done; OTOH it's possible that the whole project will be cancelled in case 
there will be not enough orders. (I won't have to pay anything in that case, 
of course.)

I know that this is a difficult project, and that I'm just buying the PCBs, 
and not a guarantee to build a working frequency shifter.
I have acess to an oscilloscope for the necessary adjustments.

My adress is:

[Full shipping adress, as it will appear on the envelope for sending you the 
PCBs]

My paypal adress is:

[your paypal adress]

========================================================================================


Looking forward to hear from you,

and don't forget the email subject line with the number of PCB *sets* (1 Set 
= 2 boards = EUR 54.00)

JH.

On 2008-02-03 23:08 +0100, JH. wrote:

> this is for all who have asked about the status of my Frequency Shifter 
> project:
> 
> I've just made a major update here:
> http://www.jhaible.heim.at/fs1a/fs1a.html

Thanks for the update. On board 1, Q2 and Q3 are either 2 x 2SA733
or 1 x 2SA1349. Neither seem easy to find. Any chance of a layout
for more mundane parts like 1 x SSM2220 or 1 x MAT03 ?

(For those who wonder what U10 and U12 are, they're MC1496.
Available from Mouser for 0.62 USD or Farnell for 1.39 EUR, take
your pick.)

-- 
Andr\ufffd Majorel <URL:http://www.teaser.fr/~amajorel/>
Do not use this account for regular correspondence.
See the URL above for contact information.

>Thanks for the update. On board 1, Q2 and Q3 are either 2 x 2SA733
>or 1 x 2SA1349. Neither seem easy to find.

You don't have to take that 2SA733 verbally. And decent pnp transistor with 
the right pinout will do.
No matched pair required. There is a trimpot to adjust the balance between 
the two expo outputs, because some of the OTA chips I tried had terrible 
matching. That trimpot will even out any transistor mismatch, too.

>(For those who wonder what U10 and U12 are, they're MC1496.
>Available from Mouser for 0.62 USD or Farnell for 1.39 EUR, take
>your pick.)

Right.

JH.

On 2008-02-04 20:00 +0100, JH. wrote:

> >Thanks for the update. On board 1, Q2 and Q3 are either 2 x 2SA733
> >or 1 x 2SA1349. Neither seem easy to find.
> 
> You don't have to take that 2SA733 verbally. And decent pnp
> transistor with the right pinout will do.
> No matched pair required. There is a trimpot to adjust the
> balance between the two expo outputs, because some of the OTA
> chips I tried had terrible matching. That trimpot will even out
> any transistor mismatch, too.

Thanks. Something else : I was wondering how hard it would be to
put N sets of boards behind the same panel for an N-voice
frequency shifter module.

The mic stuff could be left out.

The RANGE, TUNE, MANUAL and FINE pots are just voltage sources so
they could be shared.

The LIN FM pot would have to go or be replaced by N VCAs.

Replace the EXP FM pot and NORMAL/INVERT switch by a +/- voltage
source controlling N four-quadrant multipliers.

Make the NORMAL/DEEP PHASE switch an NPDT.

Replace the whole output dry/wet and feedback part by some
combination of VCAs and NPDT switches. Or, since it's for a
modular, provide just one N-way input (AUX), two N-way outputs
(SUM and DIFF) and do everything else with external mixers and
VCAs.

Did I miss something ? (Other than the fact that it's an utterly
crazy idea.)

-- 
Andr\ufffd Majorel <URL:http://www.teaser.fr/~amajorel/>
Do not use this account for regular correspondence.
See the URL above for contact information.