Reply
 
Thread Tools Display Modes
  #1   Report Post  
Posted to rec.audio.pro
gareth magennis gareth magennis is offline
external usenet poster
 
Posts: 73
Default Ampex ATR100 operating issues

Hi,

quick question.


I have an Ampex ATR100 here that when you rewind a full reel, the machine
does not brake the supply wheel once the tape runs out.
Leaving a full reel at full velocity flapping about for ages.

Should it do so?


I have read the Service Manual but can't find any reference to what is
supposed to happen when the tape runs out.
This has been reported as a fault with this machine.


I know the reel motors do not have brakes, and their primary function is to
keep the correct tension between both reels and the Capstan motor, and can
run backwards and forward to achieve this.
I would guess running backward as a brake at tape runs out should be a
feature.

The only braking I can see though, is the Emergency braking employed on loss
of power during operation, when the motors spool down by driving a lamp via
a relay opening at power loss.
I can't find these lamps to check them, where are they?


I have carried out the tension arm checks as stipulated in the manual, they
all check out fine.

What is a bit weird is that with no tape threaded, moving the supply tension
arm past midpoint causes the capstan motor to operate forwards.
I have no idea whether this is normal or not.


I have a feeling there is a problem here, but am struggling to identify it.




Cheers,


Gareth.






  #2   Report Post  
Posted to rec.audio.pro
Scott Dorsey Scott Dorsey is offline
external usenet poster
 
Posts: 16,853
Default Ampex ATR100 operating issues

Gareth Magennis wrote:
I have an Ampex ATR100 here that when you rewind a full reel, the machine
does not brake the supply wheel once the tape runs out.
Leaving a full reel at full velocity flapping about for ages.

Should it do so?


If you put your finger on the righthand tape guide and pull it toward you,
does it stop?

I have read the Service Manual but can't find any reference to what is
supposed to happen when the tape runs out.
This has been reported as a fault with this machine.


When was the tension adjustment last done on this machine? You will need a
scope and a tentelometer... you CANNOT do the adjustment with fish gauges
like you can with the 440. Go through the whole tension procedure and you
will either find that the problem is solved or you will come to a point
where you can't get some adjustment to come in at all.

This is likely the result of one of the tension servo loops having drifted.

The only braking I can see though, is the Emergency braking employed on loss
of power during operation, when the motors spool down by driving a lamp via
a relay opening at power loss.
I can't find these lamps to check them, where are they?


They are 211 lamps, I believe they are under the top cover. I have never
seen one fail, ever. Your problem is not braking, your problem is a servo
slamming full-on.

I have carried out the tension arm checks as stipulated in the manual, they
all check out fine.


Does this include all the servo adjustments or did you just check the arms
with the tentelometer?

What is a bit weird is that with no tape threaded, moving the supply tension
arm past midpoint causes the capstan motor to operate forwards.
I have no idea whether this is normal or not.


That's how it's supposed to work! You move that, the transport thinks there
is too much slack on the supply side, so it moves the capstan forward to
equalize tension between both sides.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."
  #3   Report Post  
Posted to rec.audio.pro
gareth magennis gareth magennis is offline
external usenet poster
 
Posts: 73
Default Ampex ATR100 operating issues


I have carried out the tension arm checks as stipulated in the manual, they
all check out fine.


Does this include all the servo adjustments or did you just check the arms
with the tentelometer?



***********************



This procedure was just to check the tension arm sensors were reading the
position of the arms correctly.

All done on a 5v go/nogo reading from testpoints 5/6 on the Reel Servo PCB
as per manual.




I don't have a tentelometer.

I might get one, though.




Gareth.

  #4   Report Post  
Posted to rec.audio.pro
Scott Dorsey Scott Dorsey is offline
external usenet poster
 
Posts: 16,853
Default Ampex ATR100 operating issues

Gareth Magennis wrote:
This procedure was just to check the tension arm sensors were reading the
position of the arms correctly.

All done on a 5v go/nogo reading from testpoints 5/6 on the Reel Servo PCB
as per manual.


Okay, the whole transport alignment will take an afternoon, and it will
require a scope, a tentelometer, a greenie screwdriver, and the extender
card that was shipped with the machine and ought to be in the card cage
if nobody has scavenged it.

It is a royal, royal pain in the neck. The manual has complete details on
the whole procedure. But the machine will be much easier to use afterward.

Are you located somewhere where you could have ATR come out and do it? Mike
Spitz is gone but he had a couple guys working for him who were okay. Might
be best to have someone show you the procedure.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Reply
Thread Tools
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Ampex ATR100 repair Gareth Magennis Pro Audio 7 July 21st 18 04:57 PM
FA: Ampex 300/351/351 , MM1000 and ATR100 parts Steve Puntolillo Pro Audio 0 March 19th 04 09:42 AM
FA: Ampex 300/351/351 , MM1000 and ATR100 parts Steve Puntolillo Marketplace 0 March 19th 04 09:42 AM
FA: Ampex 300/351/351 , MM1000 and ATR100 parts Steve Puntolillo Marketplace 0 March 18th 04 06:44 AM
FA: Ampex / ATR Services ATR100 I/O Modules Steve Puntolillo Pro Audio 0 March 17th 04 06:46 AM


All times are GMT +1. The time now is 11:46 PM.

Powered by: vBulletin
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 AudioBanter.com.
The comments are property of their posters.
 

About Us

"It's about Audio and hi-fi"