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Can I fix this old Pioneer SR303 Reverb myself?

mikehende

Dec 22, 2006
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I am seeing a minus sign to the left of the display numbers on the TP5, no minus sign on the TP4
 

kellys_eye

Jun 25, 2010
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Measure the voltages across R118 and R119 respectively and with respect to the chassis.
 

mikehende

Dec 22, 2006
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I've been looking and looking and locate R118 in the schematic, can you lead me to it according to the screenshot please?

r119.png
 

bushtech

Sep 13, 2016
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To the left of your R119 is a line going up, follow it R21, C44, C43, R120 and R118
 

mikehende

Dec 22, 2006
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Truly sorry this is taking so long but I look and I look and I look on the circuit board but can't see anything with the numbers R118 and 119 next to it.

I am also trying to position the unit's circuit board in accordance to the way the schematic is laid out so it will be easier for me to locate whatever but having difficulty with that too.
 

bushtech

Sep 13, 2016
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The schematic and circuit board do not look the same. Look in the manual for something like wiring diagrams showing the actual layout of the board
 

bushtech

Sep 13, 2016
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In the manual it's page 14 of 16. In the top left hand corner is the transformer. A red line leaves the top right hand side of the transformer and goes through R1. Follow that red line. It goes to point 2. From 2 go up through D11 and right above D11 is R118 and R119
 

mikehende

Dec 22, 2006
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I appreciate your help guys but I am not getting this, If I have to follow the instructions given here I will need to ask very detailed questions step by step and that might only frustrate you guys and myself. Maybe if there might be a simply course on reading schematics somewhere I can first try that?
 

mikehende

Dec 22, 2006
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On 2nd thought, I will simply take to a local Tech, will report back on what he tells me, sorry for the trouble.
 

mikehende

Dec 22, 2006
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A LOT, I would to need baby steps to go through this but to answer your question, by saying "A red line leaves the top right hand side of the transformer and goes through R1" , are you referring to the orange colored "wire" which is leading out of the transformer and connected to that connector showing as "2" on the circuit board where my red arrows are showing?

https://s14.postimg.org/udbx6aug1/red_line2.png
 

bushtech

Sep 13, 2016
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Yes, The red line is marked OR in the transformer which presumably stands for orange. Page 14 should closely resemble your actual circuit board layout so you should be able to find the 2 resistors from that.
 

bushtech

Sep 13, 2016
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Those two black cylinders with the purple rings are the 2 diodes and just to the right of them you can see two orange resistors. I cant see numbers on your photo but I'm pretty sure those are R118 and R119
 

davenn

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Sep 5, 2009
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Do you mean those 2 orange thingys [resistors?]which the red arrows are pointing to and if yes, I would need to touch their tips with the Red lead from the MM with the black lead on the chasis?


no, they are electrolytic capacitors

looking at the PCB and seeing that the part numbers are not labelled, this is probably a bit much for you to follow
If the parts were labelled it would be so much easier to guide you

taking somewhere for repair would be good
but before that
1) what is the value of this unit ?
2) repair prices are high, doesn't take much to reach the cost of many electronic items these days ... often cheaper to buy a replacement ( and you get xx months of warranty)
3) if you do decide to take it somewhere ... find out what the quote fee is, then decide if it is worth it to get a quote for the repair


Dave
 
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bushtech

Sep 13, 2016
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davenn is spot on with good advice. Thanks Dave.

If you're up for a challenge or want to get into electronics we can carry on.
Just a comment on your last photo: You have drifted away from point 2. Point 2 is over to the left on your photo. Above point 2 you see 2 big black cans (Capacitors) D11 and D17 are between those 2 caps and the resistors are just above them. Follow the lines on the board, that's where the electricity goes
 

mikehende

Dec 22, 2006
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looking at the PCB and seeing that the part numbers are not labelled, this is probably a bit much for you to follow, If the parts were labelled it would be so much easier to guide you
taking somewhere for repair would be good but before that
1) what is the value of this unit ?
2) repair prices are high, doesn't take much to reach the cost of many electronic items these days ... often cheaper to buy a replacement ( and you get xx months of warranty)
3) if you do decide to take it somewhere ... find out what the quote fee is, then decide if it is worth it to get a quote for the repair Dave

You are spot on Dave! To answer the above, yes, that is exactly what I advise my pc repair customers regarding older units. I can get one in excellent condition for 125-150 and I know it will cost around the same for a local repair so the question is do I take for repair or get a working replacement which will cost the same?

I am thinking might be better to get the repair so I can know exactly what the problem is and should the same problem re-occur as often does then I might be able to repair the 2nd time myself, what do you guys think?

Bushtech, as Dave said since labelling is one issue for me and as I mentioned a few times here, I have no issues trying the troubleshooting, my only concern is how much patience you guys will have as I will need to ask way too many questions which most likely will frustrate you guys and that wouldn't be right for me to put you guys through that, that is my only issue with this.
 

kellys_eye

Jun 25, 2010
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Honest of you to be so forthright in your limitations regarding this repair and one of the first things I searched when reading this thread was the price of replacements and I saw some starting at $50 on eBay.... you could be lucky!

But fixing a specific issue to get this one working doesn't mean that any subsequent fault would be 'straightforward' as a consequence.

But just getting readings from two resistors has taken 12+ posts! Getting to the nub of the issue.....???

I think your idea to take it to a 'pro' would be the correct decision. What we can offer is that it shouldn't take a reasonably competent engineer more than an hours chargeable labour (assuming this is the base minimum period? - half hour would be more appropriate if they do it to this level) to identify the fault. Perhaps the same again to fit the replacement part - I still reckon it's the BB Delay Line!

If this fits with your finances then go for it.
 
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