It takes around 3 minutes for relays to click in. Before clicking the relays make a lot of vibrating noise for 20 seconds or so.
There are two relays in there, one at the front and one behind the power supply capacitors. The noise is coming more from front relay as compared to the rear one.
I have also noticed that once the relays have clicked from "cold start", switching amplifier on and off with in one minute or so, they work as intended.
Once clicked the amplifier plays absolutely fine. I have
1- Cleaned all the pots and switches with servisol.
2- Replaced total of 4 caps which were showing high ESR
3- Checked for Bias and set it to 20mv
4- Checked for DC at output throughout the 3 minutes process and it is less than 7mv on each channel as measured between ground and centre leg of 0.33ohm resistor/one leg of coil.
Omron G5R-2282C-PA (Front Relay)
Omron G5R-2284P-PB (Rear Relay)
Can someone please help me with this problem?
Pioneer A-400 Stereo Integrated Amplifier Manual | HiFi Engine
Many Thanks in advance
There are two relays in there, one at the front and one behind the power supply capacitors. The noise is coming more from front relay as compared to the rear one.
I have also noticed that once the relays have clicked from "cold start", switching amplifier on and off with in one minute or so, they work as intended.
Once clicked the amplifier plays absolutely fine. I have
1- Cleaned all the pots and switches with servisol.
2- Replaced total of 4 caps which were showing high ESR
3- Checked for Bias and set it to 20mv
4- Checked for DC at output throughout the 3 minutes process and it is less than 7mv on each channel as measured between ground and centre leg of 0.33ohm resistor/one leg of coil.
Omron G5R-2282C-PA (Front Relay)
Omron G5R-2284P-PB (Rear Relay)
Can someone please help me with this problem?
Pioneer A-400 Stereo Integrated Amplifier Manual | HiFi Engine
Many Thanks in advance
The schematic is hard to read, C508? in particular, 47uF/50V. This is part of the power supply for the relay, if bad the relay will chatter or buzz until the DC voltage comes up.
Craig
Craig
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@llwhtt
@rayma
you guys rock.
I changed C508, 47UF capacitor and problem is solved.
old capacitor read 41uf ESR of 1K😱
I hope this thread helps someone in my predicament
Happy new Year and Best Wishes
Sajjad
@rayma
you guys rock.
I changed C508, 47UF capacitor and problem is solved.
old capacitor read 41uf ESR of 1K😱
I hope this thread helps someone in my predicament
Happy new Year and Best Wishes
Sajjad
I see that all of the time, OKish capacitance but lousy ESR.
Do you know where Tathwell Lincolnshire is? That's where my heritage starts I think.
Craig
Do you know where Tathwell Lincolnshire is? That's where my heritage starts I think.
Craig
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Tathwell is in the same district as me, East Lindsey District. It's around 13 miles from where I live.
If you ever decide to visit Tathwell, we should meet up.
Best Wishes