RT-707 Pause adjustment

BobbyN

BobbyN

Well-Known Member
Hi all, Looking at the service manual I see with pause on the pinch roller should be 1.5 to 2mm from the capstan. I have two 707's and on both of them with pause on the pinch roller is not even close to that. They are both basically the same distance as the "stop" position. I've watched a few videos on you tube and see that some are the way mine are and some appear to be as the manual states. One of my 707's I bought from a friend that bought it new so I'm pretty sure it had not been "messed" with in the past.

I'm curious about this. I can see that if the roller is 2mm from the capstan it should go into play more quickly and smoothly.

I sure would appreciate an opinion on this.

Thank you very much. Bob
 
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Just my $0.02 here on this but I'm sure that, once every original RT-707 & RT-701 reel to reel deck left the manufacturer the 'pause pinch roller' on all those reel to reels were all at one time or another set according to the manufacturers original specifications (1.5-2.0mm) but keep in mind this was done several decades before.

Over a period of time, after years of usage and wear it is a known fact that eventually "drift" or "drifting out of spec's" (as it's known in the calibration world. I'm a recently retired Metrologist (not a Meterologist there is a huge difference)) would have an effect on this. Yes not every RT-707/RT-701 that were used (or currently in use) were used in the same way. Some encounter heavier usage than others, etc.

So yes, keeping in mind, over a period of time all things being used will eventually come out of its original specifications and that applies to just about everything.

But if your unit is working flawlessly and everything on it works as it should/fine then I would see no reason to mess with trying to adjust/fix/etc. something that does not need to be messed with. Again, that's just me but if you strongly feel the need to adjust anything on your unit, good thing you have the specifications to go by.
 
R-2-R said:
Just my $0.02 here on this but I'm sure that, once every original RT-707 & RT-701 reel to reel deck left the manufacturer the 'pause pinch roller' on all those reel to reels were all at one time or another set according to the manufacturers original specifications (1.5-2.0mm) but keep in mind this was done several decades before.

Over a period of time, after years of usage and wear it is a known fact that eventually "drift" or "drifting out of spec's" (as it's known in the calibration world. I'm a recently retired Metrologist (not a Meterologist there is a huge difference)) would have an effect on this. Yes not every RT-707/RT-701 that were used (or currently in use) were used in the same way. Some encounter heavier usage than others, etc.

So yes, keeping in mind, over a period of time all things being used will eventually come out of its original specifications and that applies to just about everything.

But if your unit is working flawlessly and everything on it works as it should/fine then I would see no reason to mess with trying to adjust/fix/etc. something that does not need to be messed with. Again, that's just me but if you strongly feel the need to adjust anything on your unit, good thing you have the specifications to go by.
Click to expand...
Hi RTR, Thank you for your reply. I understand about calibration and age etc however... on some "you tube" videos, the decks operate just like mine, pinch roller about an inch from the capstan in both "stop" and "pause", and others appear to be as the service manual states, 1.5mm to 2mm in "pause" and an inch or so in "stop". That's a huge difference. The deck is fine and I would not go through all the work it takes to just do that however if I have the front panel off for some reason I would like to cover all bases at that one time. Just thinking ahead because in the near future I'm going to do the LED upgrade on the direction lamps since I have one burned out, and at the same time might as well install a new counter belt.

Bob

Bob
 
Hi WE6C,

what was the state of the machine when pause was pressed? The pause gives a quick return to play as the pinch roller has less distance to travel but it is a mechanical stop which stops the pinch rollers dropping. The machine needs to be in play mode first!!! The machine original state is not clear from your first entry of the thread.

GPS16
 
GPS16 said:
Hi WE6C,

what was the state of the machine when pause was pressed? The pause gives a quick return to play as the pinch roller has less distance to travel but it is a mechanical stop which stops the pinch rollers dropping. The machine needs to be in play mode first!!! The machine original state is not clear from your first entry of the thread.

GPS16
Click to expand...
Well I don't remember but just now tried it since it's playing and it worked as it should, 1.5mm to 2mm!!! It's working properly now! Thank you for bringing that up to me. Now just to make sure it's nothing intermittent, I'll try it a few times over the next few days and report back.
Thanks again and Happy Thanksgiving!
Bob
 
WE6C said:
Well I don't remember but just now tried it since it's playing and it worked as it should, 1.5mm to 2mm!!! It's working properly now! Thank you for bringing that up to me. Now just to make sure it's nothing intermittent, I'll try it a few times over the next few days and report back.
Thanks again and Happy Thanksgiving!
Bob
Click to expand...
Update, the deck will properly go into pause but it appears it ,must be in play for several seconds otherwise the pause roller position is the same as stop. My second 707 will not go into the proper pause mode no matter how long it's been in play mode. The second deck's roller position is always the same position in pause as stop no matter what I try, roller about an inch from the capstan.
Any thoughts?
Thank you. Bob
 
Hi WE6C,

I must add that I only ever used the PAUSE button during recording as it leaves the Bias Oscillator and all the Rec relays set ready to fly. It was hardly, if ever used during playback.

Cheers.

GPS16
 
Hi WE6C,

sounds like the solenoid is not pulling in for some reason. May be dried out grease issue. A bit of further investigation into it's innerds is required. As long as the Pause Solenoid coil has not gone open circuit, it is highly likely that it will be a mechanical problem. There are 2 transistors involved but check it mechanically first.

GPS16
 
GPS16 said:
Hi WE6C,

sounds like the solenoid is not pulling in for some reason. May be dried out grease issue. A bit of further investigation into it's innerds is required. As long as the Pause Solenoid coil has not gone open circuit, it is highly likely that it will be a mechanical problem. There are 2 transistors involved but check it mechanically first.

GPS16
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I've got some studying to do. I'll first figure out if the transistors are commanding the pause position or not. I'm good with diagnosing those kinds of things but mechanically these decks are foreign to me. Mechanically can this be dealt with with just/only the front faceplate off?

I also rarely use pause during playback but often during recording.

Thank you, Bob
 
Hi Bob,

the mechanism is visible when the front panel has been removed. If you have had the front panel off before, nuff said. If you have not, remove the top casing. then there are small cross head screws on the top and bottom edges. There are also 2 larger screws near the reel tables. For the small screws, make sure you use a screw driver which is a good fit or you will round them off. After the front panel had been removed I used to hold the meters with elastic bands to stop them dangling about. If you are moving the machine to different orientations during your task the meter make take some jip if you leave them dangling on the wiring.

When the front panel has been removed, the pause solenoid is a small one just above the larger Pinch Solenoid. They are near to the Supply reel (LHS). Give the mechanism a course of looking at and see how it operates. If you are lubricating any parts make sure that no lubricant gets any where near to the reel hub brake bands. Getting them clean if you do will be a nightmare as the friction material is felt and any lubricant will soak in!!!

See how you go.

GPS16
 
Hi GPS16, Yes I have had the front off to change the counter belt. Pretty easy. Between your explanation and my service manual I'll be able to figure it out. The original deck now has the pause properly working after playing for a while and giving the pause some exercise. Once it works properly it seems to continue to work properly but it does not right away. Deck number two will not operate the pause properly at all, no matter what I try. I'll make sure they get new counter belts and LED's for the direction lamps while in there.

I greatly appreciate all of your advice!

Bob
 
Bob - If I may ask, was the counter belt pretty straight forward to replace once the front panel is off or is more dismantelling required. Mine needs a belt, which I have, but haven't tried replacing yet.
My pause is about 1" away from the pinch roller by the way.
 
Old Ears too said:
Bob - If I may ask, was the counter belt pretty straight forward to replace once the front panel is off or is more dismantelling required. Mine needs a belt, which I have, but haven't tried replacing yet.
My pause is about 1" away from the pinch roller by the way.
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Good morning Old Ears Too, It's been a while since I did the belt but what I do remember is with the front panel off I believe I took the counter loose also. Again if I remember correctly the counter screws were accessible. After that it was a lot of "finesse" I think some others should chime in on this one since it's bee quite a while for me.
Have you had the front panel off B4? You know about the rubber band trick for the pinch rollers?

More about the pause, I have now figured out this pause thing on mine areis not out of the ordinary. Must be an age thing. I just learned another thing this morning. At first the pause was not working correctly. I went from pause to play several times, about 2 seconds in each "mode" I did hear a very faint sounding mechanical "click" once going into play from pause, then the pause worked as it should. This tells me 99% that it's mechanical and as GPS16 said above, lubrication could be the cause.

Let me know how you do and what you find about the pause.

Bob
 
Bob - Thanks for the reply. No, I've never had the front panel off my deck. I'm the original owner and it's never been apart. I don't have a clue as to what the rubber band trick is for the pinch rollers either.
I will try to exercise the pause function some more, as I remember that it used to be a lot 'tighter' to the capstan than it is now. Old age has set in for both me and my deck I'm afraid. It hasn't been used all that much in recent years so that may well be the problem.

Scott
 
Hi Scott,

when you remove the front panel the 2 VU meters just dangle on the wires. If you let them clatter about while you work on them at best you will lose the lamp, at worse you may lose the VU meter itself. There are springy fingers behind the meters which old them in place in the cut outs in the front panel. By this method the meters will self centre on assembly. Just use rubber bands to anchor the meters to the hardware that is behind the meters. You can then work on the rest of the machine without risk to the meters themselves.

Hope that is a bit of a better explanation. If you have not removed the front panel before then it does sound to be an odd description. I do admit myself.

GPS16
 
Scott, In addition to GPS16's statement above, you can use rubber bands around each pinch roller tape guide to hold them (roller and guide) all the way up. Go around one guide, over the head assembly and around the other guide.That way when the front panel comes off it will clear the pinch rollers. The front panel will be off and the pinch rollers and their tape guides will be intact. That's even mentioned in the service manual.
If you find the "pitch" control knob very tight and tuff to pull off, you won't be the only one.
Bob
 
Thanks GPS16 and Bob, not sure when I'll get around to doing this job as we're super busy with a wedding and Christmas coming up. I'll try to remember to post back here when I get to it though.

...now where did I put that belt....
 
GPS16 said:
Hi Bob,

the mechanism is visible when the front panel has been removed. If you have had the front panel off before, nuff said. If you have not, remove the top casing. then there are small cross head screws on the top and bottom edges. There are also 2 larger screws near the reel tables. For the small screws, make sure you use a screw driver which is a good fit or you will round them off. After the front panel had been removed I used to hold the meters with elastic bands to stop them dangling about. If you are moving the machine to different orientations during your task the meter make take some jip if you leave them dangling on the wiring.

When the front panel has been removed, the pause solenoid is a small one just above the larger Pinch Solenoid. They are near to the Supply reel (LHS). Give the mechanism a course of looking at and see how it operates. If you are lubricating any parts make sure that no lubricant gets any where near to the reel hub brake bands. Getting them clean if you do will be a nightmare as the friction material is felt and any lubricant will soak in!!!

See how you go.

GPS16
Click to expand...
Guys, The pics that Smurfer sent look great (THANK YOU SMURFER!) but I can't tell which is the pause solenoid from the picture.Does it show in the picture?

Thanks, Bob
 
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