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I jut built the Etap2hw kit from Winkel Newtone. Very thoughtfully put together kit, very good service. (Shipping to US $6 and less than a week.)

This is the third SKRM module pedal I have built, I built one for the mono guitar effects module and one for the stereo delay/reverb. Both from the data sheets, on vero. The delay/reverb (R02) is really nice.

When I first received the Etap2hw module I tried it in the other two pedals (impatient to hear it!). It worked but I got a moderately loud "click" after certain notes, with the echoes repeating the clicks. Not necessarily the loudest notes, not near clipping (lLED works), just every few notes an audible click that cycles through the delay line. I posted on another forum and it was suggested that Piet had programmed the module with a certain wrapper in mind... So I ordered the kit and assembled it yesterday.

I still have the exact same problem, a click that follows some notes and cycles through the delay. Any ideas? Could I have harmed the module by putting it into a data sheet circuit for the SKRM modules? Since the other builds sound fine with the other modules, and the problem is the same in the new PCB, I am doubtful that "its my soldering" or something.

I read the available Bulletins on Echotapper, did the suggested mods: removing the 2 100k resistors from the opamp inverting inputs to ground, changing the two feedback loop low pass ceramics to 220p, changing the two resistors that "pad" the inputs of the opamps. Used the suggested method of choosing S and D resistors for the FETs (the alternate values supplied with the kit worked fine.)

I can't help with the reported problem, but I vote you get a prize for the most cryptic thread title of the year!

Hi David,
Piet's eTap2HW should be OK into the datasheet circuit providing it provides both left and right inputs as both are used to generate the echoes.
I've emailed Piet to ask him directly if he has ever known this "clicking" as a problem. It would seem to me that there may be a problem on the "Experimental Noize" SKRM OR perhaps it's mains supply borne interference. I changed my 12V DC supply to a switchmode regulated unit recently and noise came down considerably compared with my original NetGear linear supply.
I assume that you are using a mains power supply and not batteries.

Regards,
Steve Mitchell

I've built four eTap2hw's and my friend Des has built at least six! and neither of us have come across a similar problem. When you say you get a click after certain notes, is this consistent, that is, is it always the same notes?

Clicks could be due to some domestic appliance like a fridge of air-conditioner switching on and transmitting a brief interference pulse through the ac wiring in your house. You could try just leaving your gear switched on and connected to the guitar and see if you are getting any clicks at random intervals and if these correlate with something switching on or off in the house.

Failing this, it could be a faulty SKRM module. You could try the Experimental Noize website http://www.experimentalnoize.com and there is a Forum for the FV-1 chip on the Spin Semiconductors website http://www.spinsemi.com/forum/index.php

Good luck!

Hi David,
I emailed Piet Verbruggen on your behalf and he says this is not a problem he has encountered himself.
Here is the email reply to me:-
#############
Hi Steve,
Thanks for helping this guy!

The approach when a problem occurs is to remove the SKRM board and to jumper both the I/O channels to assure the AMP part is running correctly (obviously after reassuring that the voltage is correct). When a problem is found there the idea is to cross the I/O channels so to allow isolating the faulty pre or post SKRM amplifier parts. If all passes the SKRM should be placed back. When problem now appears to be coming from the SKRM unit it is recommended to send it back for replacement. In his case he could directly send it to the USA source and ask for replacement. If requested I intermediate with Frank the producer.


P.s. It is always a pleasure to explain the reasons behind the stereo layout. It was selected as it enables near to 100% faultfinding by untrained people with distance support. I recall extra cost was 2.20€ a tradeoff was simply made on the cost/serviceability and the freedom of wet and dry+wet.
#############
Hope this is of help to you. The procedure for this fault finding is in the build manual.
Regards,
Steve Mitchell

Thanks everyone for pitching in!
The problem was in the module. I replaced it and it now works as advertised. The Board and everything on it was fine and was tested before adding the module.

Yes the power supply should be a good quality one. I notice one designed for computers adds "whine."

I understand better the stereo design choice... But how about the 12v? Most guitarists have pedal boards built around 9v. Why 12v and then the regulator down to 9?

Thanks again to Piet for designing this and Frank for the SKRM.

Glad you got sorted David.

I'm not sure why Piet went for the 12V option, no doubt it was for a good reason.

Cheers

Phil

It all runs quite happily on 6 vdc. Swap the 7809 regulator for a 7806.

ecca wrote:It all runs quite happily on 6 vdc. Swap the 7809 regulator for a 7806.

I'm not sure the op amps would be too happy running at +\- 3V though?

Correct Phil.
It's the FV1 that happily runs at 6 volts. I don't use op-amps do I ?
Silly Eric.