Post by r74chris on Dec 30, 2023 23:53:35 GMT
Hi all,
Could I first of all wish you all a happy upcoming new year! (30th Dec right now in UK) and I'm hoping somebody can please help me.
I have a Rowe Ami R74 that I bought a few months ago with the knowledge that there were a couple of issues.
The first is that the select pulse and latch relay does not energise on its own.
It does however latch with a gentle press and this then in turn pulls in the latch coil.
I can then select the record with both banks and these hold in.
The second issue is that I then need to gently press the start relay and hold it for a few seconds until the search unit motor has started.
From that point everything works perfectly, until I need to play another record and I need to repeat the process.
I have the service manual and I am ashamed to say it but many years ago I used to service these and Wurlitzer boxes. But time has taken it's toll and for the life of me I can't get my head around what I am missing!
I have 27vDC at the R1 coil before I give it a nudge (measured between common and the relay feed), but have no lamps in situ (shouldn't make a difference, but wanted to mention it!) If the R1 coil is given 30vDC direct it pulls in, is it simply a case of 27vDC being too low?
Could it be the contacts are too far apart, although my thought was the contacts on R1 are nothing to do with pulling the R1 coil in and the relay responsible was S1?
I understand that S1 should not be energised to pull in R1 coil or have I got that wrong?
I have tried gently pushing S1 to see if that did energise R1 coil, but to no avail.
Great advise Ron about not adjusting things and nothing has been played with from me apart from the 'nudging of relays!'
My only concern with all of the above is that somebody else has been tampering and fitted links here there and all over including some switches that have been left at the bottom with no labels etc.
If I can get round the two issues I'm happy to leave the 'mods' as it all works otherwise.
Any help with voltages or contact gaps etc would be gratefully appreciated and I'm hoping somebody knows exactly where to plug the old meter and test!!
If photos help I can post these, but apart from the odd 'mod' everything looks stock.
Thanks again in advance and all the very best,
Chris.
Got it all sorted!!
It turned out to be carbonised contacts on S1.
I thought I had checked them all, but once they were cleaned up and setup again everything works perfectly!
Tracing the cabling was fun as somebody had previously changed some wiring and also the colours, but going to gently clean all the contacts now.
One thing I would like to ask is if you feel it's ok to leave it in free play?
I have concerns about coil damage (previous work years ago on electro-mechanical pintables)
Rowe seem to intimate it can be left with the free play switch on, is the coil designed for that? Is it low current draw?
If it's an issue, then I'll tackle the credit computer and the installed MS111 coin mech. I guess the original was swopped out when it came into the UK and an S10 mech was fitted to then be swopped out for a MS111 later in life.
Thanks again and hopefully this bit helps somebody else in the future and I'd love to know your thoughts on the free play.
All the best,
Chris.
Could I first of all wish you all a happy upcoming new year! (30th Dec right now in UK) and I'm hoping somebody can please help me.
I have a Rowe Ami R74 that I bought a few months ago with the knowledge that there were a couple of issues.
The first is that the select pulse and latch relay does not energise on its own.
It does however latch with a gentle press and this then in turn pulls in the latch coil.
I can then select the record with both banks and these hold in.
The second issue is that I then need to gently press the start relay and hold it for a few seconds until the search unit motor has started.
From that point everything works perfectly, until I need to play another record and I need to repeat the process.
I have the service manual and I am ashamed to say it but many years ago I used to service these and Wurlitzer boxes. But time has taken it's toll and for the life of me I can't get my head around what I am missing!
I have 27vDC at the R1 coil before I give it a nudge (measured between common and the relay feed), but have no lamps in situ (shouldn't make a difference, but wanted to mention it!) If the R1 coil is given 30vDC direct it pulls in, is it simply a case of 27vDC being too low?
Could it be the contacts are too far apart, although my thought was the contacts on R1 are nothing to do with pulling the R1 coil in and the relay responsible was S1?
I understand that S1 should not be energised to pull in R1 coil or have I got that wrong?
I have tried gently pushing S1 to see if that did energise R1 coil, but to no avail.
Great advise Ron about not adjusting things and nothing has been played with from me apart from the 'nudging of relays!'
My only concern with all of the above is that somebody else has been tampering and fitted links here there and all over including some switches that have been left at the bottom with no labels etc.
If I can get round the two issues I'm happy to leave the 'mods' as it all works otherwise.
Any help with voltages or contact gaps etc would be gratefully appreciated and I'm hoping somebody knows exactly where to plug the old meter and test!!
If photos help I can post these, but apart from the odd 'mod' everything looks stock.
Thanks again in advance and all the very best,
Chris.
Got it all sorted!!
It turned out to be carbonised contacts on S1.
I thought I had checked them all, but once they were cleaned up and setup again everything works perfectly!
Tracing the cabling was fun as somebody had previously changed some wiring and also the colours, but going to gently clean all the contacts now.
One thing I would like to ask is if you feel it's ok to leave it in free play?
I have concerns about coil damage (previous work years ago on electro-mechanical pintables)
Rowe seem to intimate it can be left with the free play switch on, is the coil designed for that? Is it low current draw?
If it's an issue, then I'll tackle the credit computer and the installed MS111 coin mech. I guess the original was swopped out when it came into the UK and an S10 mech was fitted to then be swopped out for a MS111 later in life.
Thanks again and hopefully this bit helps somebody else in the future and I'd love to know your thoughts on the free play.
All the best,
Chris.
