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  #1  
Old 15th March 2014, 08:20 PM
bikerhifinut bikerhifinut is offline
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Default PSU3 and 2 loads

I need to alter the resistor inside the phono3, As supplied it had a 10k in series with the smoothing/reservoir capacitor inside. That was fine until I built the Aikido CF. The voltage to that is bang on, but the HT to phono3 is now down to 218 volts on the capacitor. All voltages as measured are low now.
The circuit diagram shows this resistor as a 1k, so I shall assume that will do the trick unless someone knows different.
I suppose this is a normal practice if using PSU3 to only supply Phono3S?

And what effect, if any will this have on the performance of phono3?

Andy.
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Old 15th March 2014, 10:02 PM
Richard Richard is offline
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Default Re: PSU3 and 2 loads

Hi Andy, yes the 10K was dropper for Phono3 when there was no other load (ie Pre3). Phono3 draws 5mA so changing the 10K to 1K will increase voltage approx 0.005 x 9000 = 45V which should put it closer to the design 250V, or try 3K3 etc to fine tune it. There may be some small change on Aikido so connect and check both, and adjust on test.
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Old 15th March 2014, 10:40 PM
bikerhifinut bikerhifinut is offline
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Default Re: PSU3 and 2 loads

Smashing.

Thanks Richard, confirms what I thought.

A.
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  #4  
Old 2nd April 2015, 11:58 AM
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pre65 pre65 is offline
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Default Re: PSU3 and 2 loads

I'm going to be using the Phono 3 without the Pre 3 connected for a while, so does the dropper resistor now need to be 10K.

Just checking.
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Old 2nd April 2015, 06:13 PM
Richard Richard is offline
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Default Re: PSU3 and 2 loads

Hi Philip, yes R35 or R41 inside Phono case, 1K with Pre3 and 10K without
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Old 3rd April 2015, 12:27 PM
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pre65 pre65 is offline
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Default Re: PSU3 and 2 loads

Thanks Richard.

The 10K has now been installed and once again my vinyl can be accessed.

I'm using my other pre (Audionote copy) because Pre 3 started crackling on one channel again.
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Old 18th April 2018, 10:08 PM
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Default Re: PSU3 and 2 loads

Quote:
Originally Posted by pre65 View Post
Thanks Richard.



I'm using my other pre (Audionote copy) because Pre 3 started crackling on one channel again.
After not using the Pre 3 for a long while I finally got round to sorting it out.

The coupling caps had been replaced by 0.1uf Clarity caps, but I suspected one was faulty. I snipped them out and a couple of WD Soniqs from the spares box soldered in their place.

Seems to have cured the problem.
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