Yes, I was just reading the manual and it says to use chrome tape like the TDK SA and Maxell XLII.
It is not biased for Metal tape.
jer 🙂
It is not biased for Metal tape.
jer 🙂
Hi again all you helpful people!
The 4-track is now up and running, but when recording the volume on track 2 is considerably weaker than the other three. In fact making it useless.
Getting a strong signal coming in doesn't help. I have tried running the incoming sound in the red, causing the sound to distort, but the sound still comes out silent from tape.
So, first attempt at troubleshooting:
I recorded the same drum sound on all four channels. Flipped the cassette and played the sounds back from different heads than which recorded the signal.
It seems the track 2 records normally, but plays back too low. The sound is there on tape and can be played back strong (backwards) with the cassette flipped.
Any suggestions are most welcome!
Thanks again,
Carl
The 4-track is now up and running, but when recording the volume on track 2 is considerably weaker than the other three. In fact making it useless.
Getting a strong signal coming in doesn't help. I have tried running the incoming sound in the red, causing the sound to distort, but the sound still comes out silent from tape.
So, first attempt at troubleshooting:
I recorded the same drum sound on all four channels. Flipped the cassette and played the sounds back from different heads than which recorded the signal.
It seems the track 2 records normally, but plays back too low. The sound is there on tape and can be played back strong (backwards) with the cassette flipped.
Any suggestions are most welcome!
Thanks again,
Carl
True electronic faults in signal circuitry are far less common than "mechanical issues" Have you scrubbed that head clean with a cotton bud and meths. Shine a torch on it, look at it and make sure its squeaky clean.
If the fault is electronic (does it use mechanical multiway record/play switches ?) then you are going to need a circuit to trace the signal through the playback head amp to see where the problem is.
If the fault is electronic (does it use mechanical multiway record/play switches ?) then you are going to need a circuit to trace the signal through the playback head amp to see where the problem is.
..and
old walkman units might be a good source for 4 tracks heads
...the ones with AR of course !
old walkman units might be a good source for 4 tracks heads
...the ones with AR of course !
Yes, Make sure the tape head is clean and shiny using only a Q-Tip and some alcohol.
Since you had it apart make sure that any cables have been re-seated.
Make sure that All of the wires on the tape heads are connected, especially the erase head!
Some times those can break off for what ever reason as they are very thin.
I had one break off of one of the heads on my Tascam 38 before for no reason after I had it for a while.
I had the same thing happen to the Level Meters before too.
The thing was working just fine and then one day it didn't.
I re-soldered it and now all is fine.
Start with that, else it will have to be traced back from the heads.
Typically there is only one Bias oscillator for all 4 channels, So since only one channel is not working it has to be a switch or a bad wire.
jer 🙂
Since you had it apart make sure that any cables have been re-seated.
Make sure that All of the wires on the tape heads are connected, especially the erase head!
Some times those can break off for what ever reason as they are very thin.
I had one break off of one of the heads on my Tascam 38 before for no reason after I had it for a while.
I had the same thing happen to the Level Meters before too.
The thing was working just fine and then one day it didn't.
I re-soldered it and now all is fine.
Start with that, else it will have to be traced back from the heads.
Typically there is only one Bias oscillator for all 4 channels, So since only one channel is not working it has to be a switch or a bad wire.
jer 🙂
When you flip the tape over All of the tracks will come out Backwards, and the weak track #2 will be in a different spot.
I forget the pattern for Cassettes but I am thinking that when you flip the tape over #2 should be playing back on channel #3.
I will have to look it up, but that is how it goes on reel to reel machines.
FWIW
jer 🙂
I forget the pattern for Cassettes but I am thinking that when you flip the tape over #2 should be playing back on channel #3.
I will have to look it up, but that is how it goes on reel to reel machines.
FWIW
jer 🙂
Hey everybody,
Thanks for helping out again.
1. Mooly! Yes, I have cleaned the heads (alcohol) - and I did it again, just to make sure. No difference.
2. Circuit? Fostex actually returned my email, and I now have the Service Manual. All circuits drawn out etc.
3. Pico, good tip!
4. Katieanddad, no I haven't demagnetized and have got no degausser.
4. Gerald, I should check the cables.
When flipping the tape - the weak spot does not show up in a new place. The sound recorded on track two shows up backwards on track 3 playing just fine.
That seems to me that the signal is recorded to tape correctly on all four channels, but played back weaker on track/channel 2.
/C
Thanks for helping out again.
1. Mooly! Yes, I have cleaned the heads (alcohol) - and I did it again, just to make sure. No difference.
2. Circuit? Fostex actually returned my email, and I now have the Service Manual. All circuits drawn out etc.
3. Pico, good tip!
4. Katieanddad, no I haven't demagnetized and have got no degausser.
4. Gerald, I should check the cables.
When flipping the tape - the weak spot does not show up in a new place. The sound recorded on track two shows up backwards on track 3 playing just fine.
That seems to me that the signal is recorded to tape correctly on all four channels, but played back weaker on track/channel 2.
/C
since it has a common rec/play head(switching via a quad bilateral ic like a 4066) the weak playback on track two does suggest a circuit problem.it's a good probability a weak capacitor in the signal chain.
Thanks. I suppose there is FAQ somewhere for stuff like that, but how do you spot a weak capacitor? (unless it has exploded etc). Anything I could measure with my multimeter? /C
dc on input pins of op amps is something to look for.(trace back any cap in series with input pins showing more that 0.7 vdc warrants further investigation)
also with power off look for caps that read more like low value resistors (good caps will appear like low ohms at first and gradually go to higher resistance over a fairly short time assuming no other gross faults in that stage) i should state some circuits because low value resistors are also sometimes present desoldering one leg of a questionable cap to confirm it's bad is required.
and all this with a simple multimeter
did you get schematic info?
also with power off look for caps that read more like low value resistors (good caps will appear like low ohms at first and gradually go to higher resistance over a fairly short time assuming no other gross faults in that stage) i should state some circuits because low value resistors are also sometimes present desoldering one leg of a questionable cap to confirm it's bad is required.
and all this with a simple multimeter
did you get schematic info?
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also if you have the means to generate a 400 or 1kz sine record that on all four tracks at the same level.
in playback mode with your multimeter set to the appropriate low ac volts scale you should be able to detect the signal loss.
in playback mode with your multimeter set to the appropriate low ac volts scale you should be able to detect the signal loss.
Thanks!
I get the feeling this might already be over my ability. Yes, I did get the Service Manual so I have the schematic. Unfortunately I'm not electro-literate enough to read it. And I certainly don't expect you all going through the trouble to help me. But if anyone feels like giving the schematics a quick glance or probing eye - I have included the pics that I believed was most relevant.
A 400 hertz sine wave? If 440 hz (the note A) would do I probably have a metronome/tuner that would give me a constant signal that I can record. Like said before the only tech-gear I have is a cheap soldering kit and a multimeter.
Thanks again!
/Carl
Schematic and PCB for the rec/play-section
Schematic and PCB for the mixer-section
I get the feeling this might already be over my ability. Yes, I did get the Service Manual so I have the schematic. Unfortunately I'm not electro-literate enough to read it. And I certainly don't expect you all going through the trouble to help me. But if anyone feels like giving the schematics a quick glance or probing eye - I have included the pics that I believed was most relevant.
A 400 hertz sine wave? If 440 hz (the note A) would do I probably have a metronome/tuner that would give me a constant signal that I can record. Like said before the only tech-gear I have is a cheap soldering kit and a multimeter.
Thanks again!
/Carl
Schematic and PCB for the rec/play-section
Schematic and PCB for the mixer-section
The circuits are too small to be useable but I can make out the four playback amps at the left (the opamps). There also seem to be four muting transistors on each. If any one of those is "on" then the corresponding amp will have no output.
You can make a 400Hz tone with "Audacity".
http://www.diyaudio.com/forums/soft...ing-using-audacity-get-you-started-guide.html
You can make a 400Hz tone with "Audacity".
http://www.diyaudio.com/forums/soft...ing-using-audacity-get-you-started-guide.html
Sorry for making the pics to small. I thought I made them pretty large, but maybe Photobucket did shrink them. I'll see if I can host it all somewhere else tonight./C
Hi again,
New try with everything uploaded to my Dropbox. If the pictures don't show up the links should work. I hope. Thanks/C
Here's the whole Service manual!
https://www.dropbox.com/s/zsmzdxoczbriuo9/XR5_sm.pdf
TAPE TRANSPORT REC/PLAY-SECTION
Page 31 - scematic Play/Rec
https://www.dropbox.com/s/ubbvg677ctb9jxe/XR5_sm-31playrec.jpg
Page 23 Play/Rec PCB
https://www.dropbox.com/s/foze1gbpcb3eu1c/XR5_sm-23_pcb_recplay.jpg
MIXER SECTION
Page 24 Mixer PCB
https://www.dropbox.com/s/mj9ov28wgw70iqa/XR5_sm-24_pcb_mix.jpg
Page 32 Mixer schematic
https://www.dropbox.com/s/08ix23r9ec77c0k/XR5_sm-32mixer.jpg
New try with everything uploaded to my Dropbox. If the pictures don't show up the links should work. I hope. Thanks/C
Here's the whole Service manual!
https://www.dropbox.com/s/zsmzdxoczbriuo9/XR5_sm.pdf
TAPE TRANSPORT REC/PLAY-SECTION
Page 31 - scematic Play/Rec
https://www.dropbox.com/s/ubbvg677ctb9jxe/XR5_sm-31playrec.jpg
An externally hosted image should be here but it was not working when we last tested it.
Page 23 Play/Rec PCB
https://www.dropbox.com/s/foze1gbpcb3eu1c/XR5_sm-23_pcb_recplay.jpg
An externally hosted image should be here but it was not working when we last tested it.
MIXER SECTION
Page 24 Mixer PCB
https://www.dropbox.com/s/mj9ov28wgw70iqa/XR5_sm-24_pcb_mix.jpg
An externally hosted image should be here but it was not working when we last tested it.
Page 32 Mixer schematic
https://www.dropbox.com/s/08ix23r9ec77c0k/XR5_sm-32mixer.jpg
An externally hosted image should be here but it was not working when we last tested it.
Thanks for your question. I don't know how to tell, I only know that ten years ago everything worked./C
Well, channel 2 has some output. Just considerably weaker.
Audacity! Great, I've already have it installed.
/C
Some quick checks. First make absolutely sure you have identified the faulty channel correctly.
Look at the circuit. Make sure the point I arrowed is at 0 volts DC (less than 200mv) and that the point marked SW on U203 is connecting to ground in playback (you need a scope for that). If you are not sure then as a test remove the transistor Q201 and link SW to ground.
Does it play ?
Look at the circuit. Make sure the point I arrowed is at 0 volts DC (less than 200mv) and that the point marked SW on U203 is connecting to ground in playback (you need a scope for that). If you are not sure then as a test remove the transistor Q201 and link SW to ground.
Does it play ?
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