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Anyone Remember MA7FR? — Parallax Forums

Anyone Remember MA7FR?

ercoerco Posts: 20,256
edited 2015-01-10 22:43 in General Discussion
Surely I'm the only one who recalls those numbers from many moons ago. Electronic part related. Any guesses? No Googling, please. Gordon, Mike or Tracy might recall. Certainly more vexing than my previous post about Fahnestock clips. I probably have one somewhere...

Comments

  • PublisonPublison Posts: 12,366
    edited 2015-01-02 16:02
    You forgot Phil. :)

    I have no recollection of that part number. How about a hint? Opto, transistor, tube, IC?
  • PublisonPublison Posts: 12,366
    edited 2015-01-02 16:08
    I'm going to guess something to do with Infrared.
  • ercoerco Posts: 20,256
    edited 2015-01-02 16:08
    Sorry, yes you and PhiPi and anyone over 50 stand a chance.

    Hint: Sold at Radio Shack. And I'm going off pure memory, but I think the numbers are right. The quest for my sample begins!
  • PublisonPublison Posts: 12,366
    edited 2015-01-02 16:30
    We need RS_Jim to chime in.
  • NWCCTVNWCCTV Posts: 3,629
    edited 2015-01-02 19:10
    Stereo Modulator.
  • ercoerco Posts: 20,256
    edited 2015-01-02 19:26
    It's not a catalog number.
  • davejamesdavejames Posts: 4,047
    edited 2015-01-02 20:28
    erco wrote: »
    Certainly more vexing than my previous post about Fahnestock clips.

    The Fahnestock question was an easy one.

    This one? Hmmmmm..."FR" as in "flame retardant"? As in some sort of circuit board material?
  • Duane DegnDuane Degn Posts: 10,588
    edited 2015-01-02 20:43
    erco wrote: »
    anyone over 50 stand a chance.

    I was just a lad (under 50) when erco asked the Fahnestock clip question (to which I submitted the winning answer (winning myself one million Fahnestock clips (I wonder how much I owe erco for storing them for me?))). Now that I'm over 50, I find my knowledge of vintage electronics parts hasn't increased much.

    I'm afraid I'm not going to win this round (which is probably a good thing since the prices erco gives out present all sorts of storage problems).
  • ercoerco Posts: 20,256
    edited 2015-01-02 21:03
    davejames wrote: »
    Hmmmmm..."FR" as in "flame retardant"? As in some sort of circuit board material?

    Wow, davejames quickly ascertained the answer through deduction, not direct experience! What I remembered was Radio Shack's "Archer" brand copper clad board sold for etching custom PCBs. Kind of a yellow/beige board with 'MA7FR" stamped all over it. My first PCBs were all MA7FR material, probably some other folks here too. I don't know if FR means "Flame Retardant" but that may well be the case. I haven't yet found any of my own old boards bearing this number, but I scoured Ebay and found this listing of an Archer-manufactured PCB using that material: http://www.ebay.com/itm/RADIO-SHACK-ARCHER-277-115-TIMEBASE-GENERATOR-PROJECT-BOARD-/281515757561?pt=LH_DefaultDomain_0&hash=item418ba58ff9&nma=true&si=gkSUZ7UyoAO0UJkHtfii0G%252F0fMs%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

    Photo attached. Well done, young davejames. Impressive. Most impressive!

    attachment.php?attachmentid=112622&d=1420261359
    ma7frC.jpg
    1024 x 768 - 310K
  • xanaduxanadu Posts: 3,347
    edited 2015-01-02 21:23
    I found this but didn't want to break the rules of no search engines.

    http://www.oppermann-electronic.de/html/januar_2008.html

    Experimental board with square pad areas 22,6 x 33 cm, thickness 1.3 mm. Consisting of 4 euros boards. Europe board consists of 37 x 56 square approx 1,8x1,8 mm squares. The material can not be defined precisely , there is no Pertinax and no epoxy. On the bottom side of the MA7FR name is printed , this could be a name for the platinum material.

    LPIC5424.JPG
  • PublisonPublison Posts: 12,366
    edited 2015-01-03 12:13
    Good Quiz Sir Erco. I would have never guessed.

    I would not have responded doing a Google search, but in my search, I found:

    http://www.radioshackcatalogs.com/

    Which I run into before.

    Spent two hours going through all the old catalogs for the old stuff that I could not afford as a teenager. :)

    So my two hours spent takes off my $2.00 from the twins college fund.
  • ercoerco Posts: 20,256
    edited 2015-01-03 14:47
    Those old RS catalogs are a hoot to look thru. I remembered having the '75 Arthur Fiedler catalog and had a peek for old time's sake. Jeepers, $459 for a receiver was major bucks back then! I still have the MC1401 and Mach 1 speakers I bought after college in 1982. Had to recone, but they still sound great. Not that I try to shake down the house with rumbling bass anymore.

    Slightly OT, but every time I hear Journey's "Don't Stop Believing" it thrusts me back into the early 80's when that song was the de facto standard for testing a home or car audio system's dynamic range.
  • Cluso99Cluso99 Posts: 18,069
    edited 2015-01-03 18:11
    Reading the first post, my immediate perception was that it was a valve such as the 12AX7 etc.
  • frank freedmanfrank freedman Posts: 1,983
    edited 2015-01-04 09:32
    erco wrote: »
    Those old RS catalogs are a hoot to look thru. I remembered having the '75 Arthur Fiedler catalog and had a peek for old time's sake. Jeepers, $459 for a receiver was major bucks back then! I still have the MC1401 and Mach 1 speakers I bought after college in 1982. Had to recone, but they still sound great. Not that I try to shake down the house with rumbling bass anymore.

    Slightly OT, but every time I hear Journey's "Don't Stop Believing" it thrusts me back into the early 80's when that song was the de facto standard for testing a home or car audio system's dynamic range.

    My father used to have some RS stuff in his office (60s), generally KDFC turned up and occasional vinyl. Personally I liked Manheim's Fresh Air for testing. Ever test a set of Magna-planars that way? Or Telarc's 1812 w/ live cannon to see if a turntable could handle it? Yeah, a bit further off the topical fairway.......
  • PublisonPublison Posts: 12,366
    edited 2015-01-04 09:36
    Cluso99 wrote: »
    Reading the first post, my immediate perception was that it was a valve such as the 12AX7 etc.

    That was my first reation. An obscure tube.
  • Buck RogersBuck Rogers Posts: 2,185
    edited 2015-01-04 10:11
    erco wrote: »
    Surely I'm the only one who recalls those numbers from many moons ago. Electronic part related. Any guesses? No Googling, please. Gordon, Mike or Tracy might recall. Certainly more vexing than my previous post about Fahnestock clips. I probably have one somewhere...

    Hello!
    I'm probably late to the party, but at a guess, a specie of printed circuit board. FR refers to the specifications on it being flame resistant. MA7 might be for its job description.

    Once a long time ago RS produced an excellent line of boards, the user would then scour their racks to find the components and eventually assemble it. They even sold an entire board to build a keyboard, as for what it would be used with, that they didn't say.
  • Buck RogersBuck Rogers Posts: 2,185
    edited 2015-01-04 10:13
    frank freedman wrote: »
    My father used to have some RS stuff in his office (60s), generally KDFC turned up and occasional vinyl. Personally I liked Manheim's Fresh Air for testing. Ever test a set of Magna-planars that way? Or Telarc's 1812 w/ live cannon to see if a turntable could handle it? Yeah, a bit further off the topical fairway.......

    Hello!
    Oh yes. Telarc released a copy of Handel's "Music for the Royal Fireworks" as recorded for the Cleveland Symphonic Winds. It was one of the first Digital recorded LPs and was a great test of any new system.
  • GordonMcCombGordonMcComb Posts: 3,366
    edited 2015-01-04 11:20
    I didn't recall the material name for circuit board stuff.

    On the "FR" I had always assumed the "F" had something to do with fiberglass, but flame retardant sounds more plausible. Some board materials (I recall Bakelite?, others?) could burn and give off toxic gasses.
  • SapphireSapphire Posts: 496
    edited 2015-01-04 11:27
    Gordon,

    Bakelite is not flammable. That's one of its special properties that make it so valuable. Doesn't burn or melt either. An amazing discovery by Leo Baekland in 1907.
  • RDL2004RDL2004 Posts: 2,554
    edited 2015-01-04 12:04
    The first time I heard "FR-4" I immediately assumed it meant fiberglass reinforced, but soon learned it actually stood for "fire retardant".

    Funny thing - just out of curiosity, I Googled MA7FR, didn't get many hits at all, but the 2nd result was this thread.
  • RS_JimRS_Jim Posts: 1,766
    edited 2015-01-06 06:47
    Funny thing that part number 277-115 has been reassigned to the bo-bot robot kit!
    Jim
  • ercoerco Posts: 20,256
    edited 2015-01-06 10:55
    RS_Jim wrote: »
    Funny thing that part number 277-115 has been reassigned to the bo-bot robot kit!
    Jim

    That is a funny coincidence! http://www.radioshack.com/parallax-boe-bot-robot-kit-usb-version/2770115.html#q=parallax%2Brobot&start=7
  • AleAle Posts: 2,363
    edited 2015-01-10 22:43
    Bakelite is so easy to synthesize and so a fitting example that still to this day it is used as a lab exercise on chemistry courses.
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