My 9090DB Story

My dad purchased the receiver new back when. He passed away 20 years ago, and the unit has been sitting in my parents’ house until my mom’s passing this March. My brother, who currently owns the house, said I should take the receiver or he was going to trash it. I brought it home with me and started to do some Google searching and found this forum. Which I am glad I did. While I was trying to decide what to do with the unit I reached out to a company in the northwest. After sending a couple of pictures they made a generous offer to buy the unit but the shipped would be a killer from Atlanta. I continued to read this forum. As a side note I am amateur (HAM) radio operator and just so happen I have all the necessary equipment to work on the receiver. So, I decided to re-cap, EC only, the receiver. Also, since a new PCB was available for the F2624 Driver build a new one. I place two orders for the parts the first to cover just the F2624 build and the second for all the other ECs. With the second order when it was received I separated the parts into a series of “mini-kits” I bagged all the ECs for each board. Along the way I also changed out the bulbs for LEDs. All parts were ordered from Mouser, Digikey or Arrow except for the LEDs which were from eBay. As of this posting I am almost finished with the recap work. I have included some pictures. The first two are the as is condition of the unit. The third is a “progress” picture with just a few ECs left to go.
 

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I like hearing stories like this, so cool to have your Dad's Sansui. It looks to be in exception cosmetic condition.
Just a bit of a dusting and good as new.
I heavily suggest you do the work to the Dolby board by pinning and soldering the pass-throughs, then you will have reliable operation with no channel drop out...
 
After you restore it you could sell it for big bucks on Craigslist. This unit is highly sought after.
 
Yes the Dolby broad has has all the pass-thoughs re-soldered, ribbon cable replaced and wipers cleaned. Also all the surfaces have been cleaned. Cleaning of the whole unit in general consisted of first 409 (spray and wipe), then 99.9% Isopropyl (spray and wipe) and finally "canned" air dried.
 
Nice project. good for another 25 years.
I'd never let it go for any money. But I bet you become an addict like me. And you'll need some good vintage speakers to mate it with.
This is just the beginning, sit back and enjoy the ride.:rockon:
 
Hang on to that. Unless you are starving and need to raise some cash, once you've finished the work you are doing to it, it will be a rock solid receiver for years to come. The history of this particular 9090DB makes it all the more valuable on a personal level. You fant buy that quality new, and to buy another 9090DB restored (if you sell this one and later regret it) will set you back some serious coin.

A lot of collectors venerate the G series quite heavily (with good reason) and while they are very good, I have to say the 9090DB - with all idiosyncracies properly addressed - is one heck of a nice receiver worthy of center stage in any vintage hifi setup.
 
Just finished the recap. Now onto re-assemble. BTW I own a pair of DCM TF-250. Purchased them from a dealer, outside of Tuscon I was living in Phoenix, about a year before they when full consumer and were available at Circuit City. Still some the best sounding speakers for the price I have ever heard.
 
That looks like a beauty. It's great cosmetics along with it's history makes it a real keeper. With the work you have done, it will serve you until you can pass it on to your kids.

We are trying to track production changes in this series of receivers. Can you post the serial number and answer a few questions about it's construction?

It looks like the chassis is silver zinc plated.
Did the original driver board have round transistors or black diodes mounted at the top of the heat sinks?
Does the protection board have fuses on it?
There is a small power supply board just to the left of the tuner board. Sansui changed the position of the filter cap on that board several times during production. How was yours mounted?
The Dolby board connects to a bank of push switches. Was yours connected with green flex pc board or black ribbon cable?

This information will be recorded in the Sansui Serial Number Database.

- Pete
 
Just finished the recap. Now onto re-assemble. BTW I own a pair of DCM TF-250. Purchased them from a dealer, outside of Tuscon I was living in Phoenix, about a year before they when full consumer and were available at Circuit City. Still some the best sounding speakers for the price I have ever heard.

Joe I own a bone stock 8080DB that I sometimes run with fully restored DCM QED's, new bottoms and tops as well and a great combination. Guy that lives down the street from Bob Crites re did em. Enjoy that 9090DB! Al
 
Okay here is the latest update on my project. The recap is complete, the relamp is complete and assembly for testing is complete. Would like to get some advice on what to watch for on the FIRST power up after all this work?
 

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Start with 60 watt. Once you have established that the unit is stable, go to 100 watt. These need to be plain, conventional incandescent bulbs. Don't use CFT, led, halogen or other types of bulbs.

What you should see when you turn it on, the bulb should flair bright and almost immediately dim to a very low level. If it stays bright for more than a couple of seconds. Turn it off. That usually indicates you have shorted output transistors.

If it dims down but remains in production mode, next step is to measure DC offset. Measure the DC voltage between chassis ground and the blue and the gray wires coming off the bottom of the power supply board.

- Pete
 
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