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Realistic TR-3000 / Teac X3 - No Signal from the Line Out Jacks

zackmc

zackmc

New Member
I aquired a Realistic TR-3000 last week. It needed a new capstain belt. I ordered one directly from Teac. Cleaned everything up. Everything with this machine is working as it should. Except for one thing. There is no signal coming from the Line Out jacks on the rear of the machine. I looked at the service manual. There wasn't anything in there that was helping me find my way. Could it be as simple as one of the several fuses in the machine? Has anyone ran across this issue? I'm hoping it's something simple. Any help would be greatly appreciated!
 
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Do the meters bounce when you play back a tape? Do you happen to have the tape-source switch set to source instead of tape? (I've done that.)
 
Meters bounce. When I run a signal Line In meters bounce. Headphone output works fine. I can monitor the Tape, and the line in source.
 
Something else to mention about the output issue. I'm not getting any hiss, or noise from the output. It is as if it's completely dead. I swapped all the fuses. That didn't seem to make a difference.
 
Since it's both channels my first suspect would be something's up with the 12vdc supply for the relay coil of K301 and the U101 ic chip. Should be 12vdc coming from the emitter of Q302 going to one side of the relay and to pin 15 of the U101 IC. If it's not there in play mode maybe controls are not making contact, power supply is holding back or possibly bad solder joint / cracked circuit board trace? That's a weird one for sure (to me anyway).
 
Actually looking at it a little closer I believe relay K301 is an output muting relay (or "anti-thump" relay) that delays the connection to the output jacks for a few seconds when you power up the deck to allow the electronics to stabilize, preventing any transient noise from making it to the output jacks. It also should cut any sound to the output jacks immediately when powering the deck down to prevent the same problem on that end, much like the delay relay used in many receivers and amps.

If the coil for K301 relay isn't pulling in (which it probably isn't) my first suspect would be C304 which I believe is the timing capacitor for the delay circuit. That's the 220uf 10volt electrolytic cap which should slowly charge up when the deck is powered on and turn on transistor Q302 which will flip over and ground the coil of K301 allowing it to pull in. It's probably a beat timing cap but check the voltages around that circuit anyway. If the meters light up you have the 6 volts for the timing circuit, you've probably got the 12 volts since you can hear stuff through the headphones, so most likely culprit is something in the timing circuit. Good place to start anyway.
 
Try to listen to the relay to determine if it's pulling in or not a few seconds after you power up the deck, best to do a little basic troubleshooting to determine what's working and what's not before changing out components. If the relay pulls in then the trouble is elsewhere but since it's both channels it probably isn't pulling in. Check around the relay coil connections and the whole general area around the timing circuit for bad solder joints, burn spots or cracked traces too.
 
audiojones said:
Try to listen to the relay to determine if it's pulling in or not a few seconds after you power up the deck, best to do a little basic troubleshooting to determine what's working and what's not before changing out components. If the relay pulls in then the trouble is elsewhere but since it's both channels it probably isn't pulling in. Check around the relay coil connections and the whole general area around the timing circuit for bad solder joints, burn spots or cracked traces too.
Click to expand...
 
I'm a little late to the party but I've had this problem with my X3 Mark II as well. Please note that the X3 and the X3 Mark 2 are different. U101 on the X3 is U102 on the X3 Mark II. You must have the proper schematic diagram to properly look at the X3 Mark II. The back panel, the RCA plug panel, and the bottom panel are needed to be removed to gain access to the relay is at the end edge of the circuit board towards you. Unfortunately you can't hear the the relay click in as it just doesn't make any noise. In researching these solenoids they seem to be extremely reliable, with a lifespan of up to 40,000 hours. The real problem turned out to be the timing circuit that delays the relay to avoid the pops and crackles when the recorder is first turned on. The 220 microfarad 10 volt electrolytic capacitor C303 is usually the problem. The 2sc-945 transistor is also very reliable. I switched my 220 microfarad cap out for one on hand with a 25 volt rating and the problem went away. The cap is easy to reach and easy to unsolder and remove and replace. I would definitely start there first.
 
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