Realistic STA-225 repaired

[BrewDude]

Around $60-80 and a few weeks working on it in my spare time -- I have my "given to me" STA-225 working really well. $22 of that cost was for a service manual -- just couldn't find a schematic anywhere for it.
Bought the service manual from Sam's Technical.

Replaced all electrolytics, (4) Output transistors, and various other TO-92 package transistors.

Initial problem was no output on either channel.
Left channel had 36 VDC on speaker output and right channel had about 500mv.
Bad drive transistor was shorted (causing 36v on output) and both left channel output transistors were blown.

Went ahead and replaced the differential pair transistors on both channels which got me to around <50mv DC offset on both channels-- not excellent, but not terrible.

Just need to clean everything really well and lubricate pots, switches.
It is really a nice receiver from Realistic..I've read before that the tuner is pretty decent..

This is going to be my garage stereo powering a pair of Cerwin Vega D1s -- while a brew beer.

 

[bradfro]

I love this receiver, I would like to find one as well. This was the TOTL for Radio Shack for years in 70's. I dreamed about owning one as a kid in the 70's

 

[Rey1]

I have one, but I haven't really used it in a couple of years. It's a great sounding receiver, but FM Stereo seems to be out in mine (every FM signal comes through in mono).

 

[hnash53]

I had this receiver awhile back and thought that the "quatravox" setting was super on this receiver. I used it for awhile as a home theater receiver using the quatravox setting and I heard distinct sounds emanating from the rear speakers.

Overall, I think this is great vintage receiver.

 

[rcaman]

i have one also they are very nice receivers. plenty of power.

 

[BrewDude]

I love this receiver, I would like to find one as well. This was the TOTL for Radio Shack for years in 70's. I dreamed about owning one as a kid in the 70's

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I saw one sold on Ebay recently -- think it went for around $125 - $135. Keep your eyes on ebay and craigslist -- you might find one.

 

[Gypsy Brown]

I JUST got an STA-225 and replaced the fuse on the back plate and got it to turn on, but hooked up speakers and all I got was loud buzzing and my 15s flexing inward like they were going to blow. I'm still educating myself on these recievers and was delighted to discover this stereo is INDEED worth the restoration. But idk where to start other than audio output. Any advice on how to troubleshoot (what/where, etc) and what I should replace would be VERY helpful. I'm getting tired of looking at my larger than life (for today's standards anyhow) Coral BX-1500 6-way 15 inch cabinets on mute. Help please! Thanks guys!

 

[petehall347]

offsets could be tweaked but i dont think its needed here.