[Milsurplus] Wideband Receivers R-1039 and R-1151 ???

[Ray Fantini]

The Ampex FR-900 and the role they play in the Lunar Orbiter Image Recovery Project (LOIRP) may be the biggest story in Ampex instrument recording. The Ampex role in audio and later video recording is legendary, although not there invention they were the first American manufacture and for decades produced the best audio and later video recorders for Broadcast, music production or any audio application. You would have thought that the money they generated from any of their divisions would keep them in business forever but they were another one of the companies like the RCA Broadcast division that went out of business almost overnight. Unlike RCA Broadcast that missed out on the digital revolution in the eighties Ampex was at that time a leader in digital production equipment but somehow that all fell apart.  Like the part in the NSA article about Ampex being a manufacturer of dynamotors in WW2 and because they had lots of experience with small motors and lots of inventory after the war that's what lead them into the tape recording business, they had to do something with all those motors and tape transports were just the thing.
Back in the seventies and early eighties when I first started working in broadcasting much time was spent working on Ampex and Magnacord transports, just like the Nems Clarke thing would like to have an old Ampex 440 around just to play around with again but way more projects then space.

Ray F/KA3EKH

-----Original Message-----
From: Milsurplus [mailto:milsurplus-bounces at mailman.qth.net] On Behalf Of mikea
Sent: Friday, December 04, 2015 10:37 AM
To: Military Surplus Mail List
Subject: Re: [Milsurplus] Wideband Receivers R-1039 and R-1151 ???

On Fri, Dec 04, 2015 at 03:15:32PM +0000, Ray Fantini wrote:
> Don't know about the NSA but NASA used lots of old Ampex and similar 
>wide bandwidth analog recorders for direct capture of the downlinks 
>from things like the Microdyne receivers. The oldest Microdyne I have 
>seen are the 1100 family but going to assume that maybe the R-1151 or 
>1039 may have been something prior to the Microdynes like those old 
>Nems Clarke thirteen hundred series radios?

I don't know about the radios at the various ground stations, though I have the E-mail address of someone who worked at the Tananarive, Madagascar (now Antananarivo, Malagasy Republic) Gemini/Apollo ground station; he may be able to tell us more. 

I do, however, know about the wideband analog recorders used at the ground stations, since we had some at the Manned Spacecraft Center, in the Data Reduction Complex on the second floor of Bldg. 12. They were Ampex FR-1400
systems: 2" tape, 14 track, .9375 to 120 IPS in 2 speed bands. Changing from low band to high band involved opening up the transport and shifting a belt from one set of pulley faces to another. Frequency response in direct mode at
120 IPS was something like 400 HZ bottom, topping out at 1.5 MHz, flat within
1 dB; in FM mode, at 120 IPS, the response was DC to 400 kHz, flat within 1 dB, and it was fairly easy to get it a lot flatter.

There were 14 slots in the record electronics, each holding one of NBFM, WBFM, or direct electronics. Ditto for reproduce electronics. 

There were 4 possible head configurations: 
o   14 track wideband
o   14 track narrowband
o   7 track wideband
o   7 track narrowband 

The wideband head stacks were very expensive and very soft; using even the best tape available (Memorex 62J), they scalloped after about 20 hours of use, and had to be sent back to Ampex for refurbishing. Using anything other than Memorex 62J was prohibited, because it would sandpaper the heads down to where the head gaps were too wide for refurbishment, and the stack would have to be discarded. The narrowband heads were very hard and very nearly bulletproof: I think I could have got away with running emery paper over them. 

The transport was a wonderful piece of design, implemented very nicely:
muscular as could be, as it needed to be to handle 9200-foot rolls of tape, and very soft indeed on the tape. The guides all had air bearings, and tension control was through feedback on the air pressure at the bearing-tape interface. 

I loved using them, and they were *SO* easy to work on. They didn't need much work, either: built like battleships, but by Swiss watchmakers. 

--
Mike Andrews, W5EGO
mikea at mikea.ath.cx
Tired old sysadmin
______________________________________________________________
Milsurplus mailing list
Home: http://mailman.qth.net/mailman/listinfo/milsurplus
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Milsurplus at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html