Jump to content
rstl99

Nagra IV-S question (time code)

Recommended Posts

Maybe I'm missing something here, but I've been wondering why you don't just remove the jumper plug from the external pilot tuchel connector. Actually, looking at the photo supplied, the pilot jumper doesn't appear to be present anyway.

The pilot and/or TC signal passed through that 4-pin connector. Unless the signal were jumped from (if memory serves) the Xtal pin to the Grnd, the signal would not carry through to the sync head. Removing it would take the sync circuit out of the path completely.

 

Alternatively, if one doesn't have the screw-on jumper plug and wanted to use sync recording. one could just bend and cut a paper clip to a U-shape and use it with a piece of tape to hold it in place.

 

David

HI David,

 

The 4-pin jumper is required for Pilotone and FM Pilot Nagras, but Nagra's timecode version of the IV-S(TC) did not require the jumper plug to record timecode to the center track. However, the jumper was required in the resolver during sync playback when using the Cooper resolver or the Nagra 2-piece equivalent.

 

gt

Share this post


Link to post
Share on other sites

Check out the Helios recording consoleshttp://www.helios-electronics.com/

Dear Al,

Thanks for your acknowledgment.

I love your expression about arguing with a fool.

Apart from Engineers Joke in my reply to Chris (Page 1 Bottom)

I have a few more Engineering one's I have picked up over the years

Try this one at your next meeting

"To the optimist, the glass is half-full. To the pessimist, the glass is half-empty.

To the engineer, the glass is twice as big as it needs to be."

Kind Regards

Tony

Helios Electronics Ltd

Share this post


Link to post
Share on other sites

Thanks Tony. I took the knobs off last night and removed a layer of grime. Also found a green felt disc (is this standard?) under red knob only which i removed and the clutch disengages more easily now (previously, it was always engaged).

Will remove my 50 strobe and post it to you tomorrow. Anyone have an exploded view parts diagram for the iv-s? I have the operating manual and schematics photocopies but an exploded view would help with some of the assembly disassembly process.

Enjoying tinkering with this engineering marvel :)

Chris

Dear Chris,

There is a saying and that is

"if it ain't broke then don't try to fix it"

But then on the other hand if they are noisy or intermittent, then I would use WD-40, but try to find a can that's near its ending, as these are easier to control the out-flow, I alway keep my nearly used cans for such occasions.

Or #-1

If your can wants to blast everything in sight then pray it into something where you are able to feed a small amount into the hole.

or #-2

Hold your finger on the end of the red tube and then press, then slowly remove the tube from the can, and use the tubes contents to feed the hole.

or # -3

Even though its painstakingly slow I spray some onto the tip of a small screwdriver and then feed the hole.

Should you want to remove the Potentiometers for cleaning then set both knobs to be ganged, turn them to zero, then undo the ganging so they are independent to each other, and make sure both are set to Zero again, now you can remove the knobs safely but be careful as the ganging cogs can crack due to age.

Please send the 50Hz to my home address in France

Mr Tony Arnold,

Les Tenons,

La Chapelle Sur Aveyron,

45230,

Loiret,

France

You can E-mail your address to:

anthony@ampex-uk.com

I will send you the 60Hz using normal post

Again the saying is

If it ain't broke don't fix it, BUT the reason it ain't broke yet, is because it don't have enough features

Kind Regards

Tony

www.ampex-uk.com

&

www.helios-electronics.com

www.arnys-shack.com

Share this post


Link to post
Share on other sites

Thanks Tony. I took the knobs off last night and removed a layer of grime. Also found a green felt disc (is this standard?) under red knob only which i removed and the clutch disengages more easily now (previously, it was always engaged).

Will remove my 50 strobe and post it to you tomorrow. Anyone have an exploded view parts diagram for the iv-s? I have the operating manual and schematics photocopies but an exploded view would help with some of the assembly disassembly process.

Enjoying tinkering with this engineering marvel :)

Chris

Dear Chris,

Regarding the exploded Parts View, not a problem, please write to me at

anthony@ampex-uk.com sending your address.

As its an A3, my printer will scan and print A3, so I will send it with the

60Hz Strobe, if your in a hurry I can PDF the Parts View to you.

Kind Regards

Tony

www.ampex-uk.com

What is the difference between Mechanical Engineers and Civil Engineers?

Mechanical Engineers build weapons, Civil Engineers build targets.

Share this post


Link to post
Share on other sites

If any of the Canadians in this thread are still looking for parts for their Nagra recorder, Audio Services Corporation (www.audioservicescanada.com) was the Canadian agent for Nagra in the glory days of the IV-S.  We still have a great stock of service parts.  I'd be happy to check stock if there is something you need.  You can reach me toll-free at the number listed on the website, or send me a PM here.

Share this post


Link to post
Share on other sites

Tony,

Found a copy of exploded view. Thanks for your kind offer though. Didn't have a chance to pack up the strobe yet but tonight i will have time. Also confirming that I'll include the set screws. Chris

Share this post


Link to post
Share on other sites

Dear Bill,

I have posted my request here as someone else might be reading my reply, who might be able to help.

I'm looking for Service Manuals or Schematics for both the Nagra-JBR & the PS-1, and any chance would anyone by chance have a Service Manual or Schematics for the SNST-R.

I'm also looking for known Mod for the Nagra JBR, this mod enables the JBR to be placed out of record and set into Fast/Forward at four times its normal speed.

This was designed by Daniel Technoligy , but I don't receive any replies these days.

Kind Regards

Tony

www.ampex-uk.com

Share this post


Link to post
Share on other sites

My last experience (years ago) with swapping strobes, is that the inner circumferences differ between the 60hz strobe and the 50hz strobe.  There's a bushing inside the strobe that rides on the transport shaft. As I recall, these cylindrical brass bushings are not interchangeable between the 50 and 60 hz strobe. 

Pete Verrando

Share this post


Link to post
Share on other sites

My last experience (years ago) with swapping strobes, is that the inner circumferences differ between the 60hz strobe and the 50hz strobe. There's a bushing inside the strobe that rides on the transport shaft. As I recall, these cylindrical brass bushings are not interchangeable between the 50 and 60 hz strobe.

Pete Verrando

Dear Pete,

I can only say from experience that as long as you use the three screws in the strobe to centre it, using anthony@ampex-uk.com Diameter Test Meter as shown on my picture below which also shows other mechanical tools that maybe required to service a Nagra.

I have changed several over the years with no problems whatsoever, the one I have serviced now

is from the USA, and will be staying with a client in Europe.

Kind Regards

Tony

www.ampex-uk.com

post-9812-0-51090900-1389313749_thumb.jp

Share this post


Link to post
Share on other sites

My last experience (years ago) with swapping strobes, is that the inner circumferences differ between the 60hz strobe and the 50hz strobe.  There's a bushing inside the strobe that rides on the transport shaft. As I recall, these cylindrical brass bushings are not interchangeable between the 50 and 60 hz strobe. 

Pete Verrando

 

Pete, I imagine that if you found a difference between in the inside diameter of a 50Hz and 60Hz strobe roller, it was a random tolerance difference and was not related to being 50Hz or 60Hz. The rollers, bushings, axles, and collets are the same. The only difference is the pattern on the disc that's pressed into the top of the roller.

 

Best,

 

Glen Trew

Share this post


Link to post
Share on other sites

On the subject of the Nagra strobe roller:

 

Like other mechanical servicing and adjustments on the 4-series analog Nagra recorders, it is VERY difficult to understand and do the procedures just by reading about them in the service manual. The two most commonly misunderstood and misadjusted are 1) Maintenance for proper tension and stability of both the supply and take-up reels, including the grease clutch and brake felts, and linkage and spring adjustments, and, 2) The strobe roller assembly, including the assembly of the strobe roller, two inner brass bushings, and axle, plus the tensioning of the collet that holds the strobe roller axle on the deck. Proper tensioning of the collet against the deck is required to give back-pressure to the linkage that is activated by the transport control lever. Proper tension is achieved when the supply-side tape guide moves first and goes "home" before the strobe roller moves, when the control lever is closed.

 

I wager that neither of these items (reel tensions and strobe roller assembly) have ever been properly on the first attempt when using the manual as a guide. I've trained several technicians on these adjustments, and its still takes a while to get it.

 

Hopefully I can put together a video to show both of these service items while there is still interest.

 

Glen Trew

Share this post


Link to post
Share on other sites

On the subject of the Nagra strobe roller:

Like other mechanical servicing and adjustments on the 4-series analog Nagra recorders, it is VERY difficult to understand and do the procedures just by reading about them in the service manual. The too most commonly misunderstood and misadjusted are 1) Maintenance for proper tension and stability of both the supply and take-up reels, including the grease clutch and brake felts, and linkage and spring adjustments, and, 2) The strobe roller assembly, including the assembly of the strobe roller, two inner brass bushings, and axle, plus the tensioning of the collet that holds the strobe roller axle on the deck. Proper tensioning of the collet against the deck is required to give back-pressure to the linkage that is activated by the transport control lever. Proper tension is achieved when the supply-side tape guide moves first and goes "home" before the strobe roller moves, when the control lever is closed.

I wager that neither of these items (reel tensions and strobe roller assembly) have ever been properly on the first attempt when using the manual as a guide. I've trained several technicians on these adjustments, and its still takes a while to get it.

Hopefully I can put together a video to show both of these service items while there is still interest.

Glen Trew

Dear Glen,

100% correct Obtaining a Nagra Service Manual is only the beginning, its worth mentioning

how so many DIY's can't figure the

Take-Up clutch adjustment and are surprised when I ask them If the 2mm Ball Bearing is still correctly

in place, and if they don't get the adjustment right they will loose this tiny Ball again .

The Circular Clock Gram Scales are very useful for checking springs and places where a pull scale

will not reach and they are are not as expensive as one would think, check eBay

LINK

http://www.ebay.com/bhp/gram-gauge

When I have finished a Nagra IV I alway make sure the pinch roller is not pressing against the

Capstan Shaft this avoids a permanent dent in the Pinch Roller during Transit or Storage

Many thanks again Glen, let me know when you've done the video,

I'm sure it will be a great help to us all

Kind Regards

Tony

www.ampex-uk.com

Share this post


Link to post
Share on other sites

I have checked the diameter of both a Canadian Nagra IV-STC and an IV-SJ so as to be sure I was not mistaken.

The Diameter of the Strobe Bearing in both cases are identical, (See the pictures below).

I carried out this test just in case anyone was a little concerned about exchanging Strobes.

The other picture below, shows that if you turn the three Screws inwards until they are exactly to the edge of the Strobe Barrel you will have a much better chance of fitting it very close to being correct, its just a matter of adjusting the three screws the same amount

Kind Regards

Tony

www.ampex-uk.com

post-9812-0-44706900-1389485385_thumb.jp

post-9812-0-02998400-1389485427_thumb.jp

post-9812-0-60997600-1389485474_thumb.jp

Share this post


Link to post
Share on other sites

Thanks for your insights Tony and Glen!

Glen, videos would be super helpful coming from such a nagra service tech like you. Wow, that is a generous gesture and shows a love of these machines and interest in keeping them operating correctly into the future. If there was ever a "intro to maintaining your iv-s" as a live/skype training camp, i'd be the first to join and pay tuition!

Chris

Share this post


Link to post
Share on other sites

Another vote of support and deep thanks (in advance) if you could find the time to produce such a video Glen!  There's so many analog Nagras (IIIs, 4.2s, IV-Ss) changing hands on the internet, and winding up in the hands of some people who either don't have the service manual or (like me) can't easily decipher and apply it to maintenance of my Nagras, that such a video(s) would be of great service, and help prolong the useful life of these wonderful machines.

  --Robert

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×