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Projects => General Questions => Topic started by: Spenzerleehorton on December 22, 2016, 03:25:51 PM

Title: Harbinger one oscillating noise?
Post by: Spenzerleehorton on December 22, 2016, 03:25:51 PM
Hi,
have just built two of these pedals the collosalus and the harbinger one.
the harbinger one works but has a loud oscillating noise when pedal is activated, this is in time with the light?
also the speed led only lights up when about 3/4 CW.
Also is there anyway to make the speed faster?

regards

Spence.
Title: Re: Harbinger one oscillating noise?
Post by: Spenzerleehorton on December 22, 2016, 03:51:26 PM
right I've sorted the speed led, taken out the 1uf and put in a 10uf, shines at all speeds now.
just need to sort this whistle oscillation!! must be a cap or can i twiddle out the oscillation?
Title: Re: Harbinger one oscillating noise?
Post by: Spenzerleehorton on December 23, 2016, 11:10:37 PM
From what I've read on here, nearly everyone has had problems with psu noise on the harbinger one and the collosalus , this does make me wonder why have they bothered to try and keep it 9v if there are so many problems?

could anyone help point out where an oscillating noise would come from please? im assuming its the power supply?
Title: Re: Harbinger one oscillating noise?
Post by: Spenzerleehorton on December 29, 2016, 07:52:44 AM
so close with this one if someone could help point me in the right direction please?
Title: Re: Harbinger one oscillating noise?
Post by: gordo on December 29, 2016, 01:59:39 PM
Quote from: Spenzerleehorton on December 22, 2016, 03:51:26 PM
right I've sorted the speed led, taken out the 1uf and put in a 10uf, shines at all speeds now.
just need to sort this whistle oscillation!! must be a cap or can i twiddle out the oscillation?

Whoa, I glossed over this one.  That's the fix??!!  I haven't had a chance to sort this one out but will give it a shot.  I used 15v on the flanger and solved all issues with it.  I don't have an appreciable amount of noise on the Harb.
Title: Re: Harbinger one oscillating noise?
Post by: midwayfair on December 29, 2016, 03:39:20 PM
Quote from: Spenzerleehorton on December 22, 2016, 03:25:51 PM
have just built two of these pedals the collosalus and the harbinger one.

I'm not quite sure I understand you. Did you build two separate pedals, or is it a two-in-one?

If it's two separate pedals, is the noise present when you use them individually (as in, NOTHING ELSE hooked up and turned off -- just guitar, pedal, amp)? What are you powering them with? If it's a two in one, you're possibly experiencing heterodyning.
Title: Re: Harbinger one oscillating noise?
Post by: Spenzerleehorton on December 29, 2016, 06:58:54 PM
hi,

yes two separate pedals, it doesnt seem as though i can twiddle away the noise with the trim pots? and yes im using 9v pump
Title: Re: Harbinger one oscillating noise?
Post by: midwayfair on December 29, 2016, 07:29:05 PM
Again, is the noise there what you try ONLY one of the pedals, guitar > pedal > amp, with no other pedals hooked up to the same power supply that you are using to power the pedal under test?

A 9V pump is not a power supply, it's a circuit inside the pedals. What power supply are you using? Is the noise there if you use a battery? What charge pump chips did you use, and does the chip that you used supply enough current to run these effects? When you audio probe, where does the noise get introduced into the pedal? Did they make this noise outside of the enclosure? Does it happen with another guitar and another amp if you have one? What about if the input of the pedal is grounded (eliminated the guitar signal entirely)?

These are very complicated projects and you have to eliminate every possible source of outside interference before you determine that it's a problem with the circuitry of the individual pedal, especially when more than one pedal is making the noise.
Title: Re: Harbinger one oscillating noise?
Post by: Spenzerleehorton on December 29, 2016, 08:15:00 PM
ah ok,
yes just guitar, pedal, amp.
i will test this on 9v battery first, then.
could be power supply so will change it if i get no noise from battery.
Title: Re: Harbinger one oscillating noise?
Post by: Spenzerleehorton on December 29, 2016, 08:21:56 PM
yep, 9v battery works fine no noise, so its power supply!!!

just need to sort this collosalus now!!!
Title: Re: Harbinger one oscillating noise?
Post by: Spenzerleehorton on October 12, 2018, 05:09:52 PM
right, i've come back to this pedal as it seems i didn't get it right last time!!!

everything sort of works but the effect level is very low and with the effect on there is a low frequency oscillating noise?
I cant seem to completely dial it out, and effect level is pretty much not there?

could anyone pin down this issue or know which part of the circuit to look at?

Title: Re: Harbinger one oscillating noise?
Post by: Spenzerleehorton on October 15, 2018, 09:35:00 AM
Had another look today and yes it's the oscillator which with intensity all the way off you can hear the pulse of the LFO, it changes with the speed control.
I can't seem to dial this out with the lamp trimmers?

Any suggestions to remove this low frequency oscillating?
Title: Re: Harbinger one oscillating noise?
Post by: HamSandwich on October 15, 2018, 04:14:16 PM
I'm not sure what to add to this, except the one I just built and excluded the charge pump (used an 18V plug) has zero noise at any setting. Perhaps there's something going on still with the charge pump? I also am wondering if having the input jack practically touching the LFO section of the circuit is causing issues. Is it boxed up? Can you move the input wiring away from the LFO section?
Title: Re: Harbinger one oscillating noise?
Post by: Spenzerleehorton on October 15, 2018, 08:27:52 PM
Ah ok so it may be the charge pump, sounds right tbh.
I have an 18v dc socket so will change and see if noise disappears.
Title: Re: Harbinger one oscillating noise?
Post by: Spenzerleehorton on November 02, 2018, 10:01:25 PM
I've changed over to 18v now and changed 3 x 100nf caps to film caps they were ceramic, don't know if that had any influence.
I will test tomorrow for noise but powers up ok.
Someone else mentioned it could be the extra draw from the led, but I think I'll leave it 18v if everything works ok now.
Title: Re: Harbinger one oscillating noise?
Post by: Spenzerleehorton on November 09, 2018, 05:52:58 AM
The hum problem seems to be solved now so I can only put it down to the power supply charge pump and running the led not off the 9v direct supply.
Title: Re: Harbinger one oscillating noise?
Post by: helos on August 06, 2019, 09:04:51 PM

[/quote]
If it's a two in one, you're possibly experiencing heterodyning.
[/quote]

heterodyning... what is this thing??