ttbccw
Active Member
Hey all!
About 10 years ago a friend of mine gave me an Optonica 5605 receiver. I have used it off and on the past 10 years, and it has worked ok and sounded ok. I have always tinkered with things and I started to do some restoration projects a few years back so I'm not a complete noob to all this. I learned a TON from the posts here! And thanks to lots of great posts and responses from Audiokarma members I was able to restore/upgrade my Pioneer SX-828...and it sounds amazing! So I always thought I would do the same for the Optionica some day.
Well, That day is here. So here is what I need some help with....if you can...
I have searched the internet for info on this receiver ever since it came into my possession. I haven't found much. Not nearly as much as I did for the Pioneer! I did find the repair manual for one..kinda..it's for the 5606 model actually. So I took the amp apart to see how different the 5605 and 5606 really are. Well...I wanted to start with the power supply and replace the power filter caps. There are 4 and....they also have 4 leads. That is the first time I've seen that or heard of that. I looked up some info on them and I think I understand what they are. It also seems to be that they are hard to find direct replacements for because of the leads. Also, it looks like Sharp put a lot of really good quality (for the time) components in here. All Nicinon caps at least. Including the power filter caps. So I decided that instead I would start with something a little simpler from the manual and look at what the DC offset and bias were. Well, this is where I noticed that the 5605 and 5606 are different. There is supposed to be 2 sets of variable resistors on the amp board according to the 5606 manual. One for the DC and one for the bias. Well, there is only one set on the 5605. And when you use the test points from the manual in the procedure the single set of variable resistors change the mv values in both test points...bias and offset. And the mv values are low for both with the vr turned all the way counter clockwise...so I don't know if I have to figure this out or if there really is a repair manual for the 5605. I am guessing I need the actual 5605 manual now...which I have been unable to find...anywhere. I have included a pic of the amp board so you can see I'm not completely nuts. If you can see the 2nd set of vr let me know!
I also read someplace that this was supposed to have some kind of hybrid output transistors, but from what I see they look normal to me.
SO...any help with this is appreciated! FOR SURE!
![IMG_20160207_092633716_HDR[1].jpg](/forums/data/attachments/559/559731-3c8f85768e94db8600ff2000ba1a7d71.jpg?hash=PI-Fdo6U24 "IMG_20160207_092633716_HDR[1].jpg")
About 10 years ago a friend of mine gave me an Optonica 5605 receiver. I have used it off and on the past 10 years, and it has worked ok and sounded ok. I have always tinkered with things and I started to do some restoration projects a few years back so I'm not a complete noob to all this. I learned a TON from the posts here! And thanks to lots of great posts and responses from Audiokarma members I was able to restore/upgrade my Pioneer SX-828...and it sounds amazing! So I always thought I would do the same for the Optionica some day.
Well, That day is here. So here is what I need some help with....if you can...
I have searched the internet for info on this receiver ever since it came into my possession. I haven't found much. Not nearly as much as I did for the Pioneer! I did find the repair manual for one..kinda..it's for the 5606 model actually. So I took the amp apart to see how different the 5605 and 5606 really are. Well...I wanted to start with the power supply and replace the power filter caps. There are 4 and....they also have 4 leads. That is the first time I've seen that or heard of that. I looked up some info on them and I think I understand what they are. It also seems to be that they are hard to find direct replacements for because of the leads. Also, it looks like Sharp put a lot of really good quality (for the time) components in here. All Nicinon caps at least. Including the power filter caps. So I decided that instead I would start with something a little simpler from the manual and look at what the DC offset and bias were. Well, this is where I noticed that the 5605 and 5606 are different. There is supposed to be 2 sets of variable resistors on the amp board according to the 5606 manual. One for the DC and one for the bias. Well, there is only one set on the 5605. And when you use the test points from the manual in the procedure the single set of variable resistors change the mv values in both test points...bias and offset. And the mv values are low for both with the vr turned all the way counter clockwise...so I don't know if I have to figure this out or if there really is a repair manual for the 5605. I am guessing I need the actual 5605 manual now...which I have been unable to find...anywhere. I have included a pic of the amp board so you can see I'm not completely nuts. If you can see the 2nd set of vr let me know!
I also read someplace that this was supposed to have some kind of hybrid output transistors, but from what I see they look normal to me.
SO...any help with this is appreciated! FOR SURE!