Re: FTGH: Unknown extender card

2018-03-04 Thread Cliff Miller via cctalk
I once owned a Motorola D2 kit with 6800 micro. I thought that pin count sounded familiar. On Sun, Mar 4, 2018 at 7:52 AM Robert via cctalk wrote: > On Sun, Mar 4, 2018 at 6:40 AM, Noel Chiappa via cctalk > wrote: > > > A couple of people have

Re: EF50 was Re: radar history

2018-03-04 Thread Noel Chiappa via cctalk
> From: William Donzelli > Germany often gets the short end of the stick when it come to radar > tech in World War 2 For those who are interested in German radar, there's a good book: David Pritchard, "The Radar War: Germany's Pioneering Achievement 1904-45", 1989 which

Re: EF50 was Re: radar history

2018-03-04 Thread William Donzelli via cctalk
:> The high frequency power tubes were required for better spacial resolution. My understanding was that major difference between the German radar and allied was that the Germans had a single trace, like a time domain reflectometer. The allies had a rotating image that is similar to what we see on

Re: radar history

2018-03-04 Thread William Donzelli via cctalk
> The one described in the RH is a "split anode magnetron". The note on > it says that "frequency stability is not very good:. Yes, but in World War 2 (and a little into the 1950s), split anode magnetrons were used in ECM "jammer" transmitters. > It's my understanding that the allies used the

Re: radar history

2018-03-04 Thread William Donzelli via cctalk
> A very interesting story in this radar history is how the Dutch managed to > rescue the EF50 tube, essential for these early radar receivers, to England > just hours before the Germans invaded holland. This is generally a good article, but has a major flaw or two. One, it describes acorn tubes

Re: radar history

2018-03-04 Thread William Donzelli via cctalk
> Ordinary magnetrons had indeed been around for a while; they were invented in > 1920. The British invention was the _cavity magnetron_, a quite different > beast; it was kind of a cross between a magnetron and a klystron, with the > best features of each. The cavity magnetron was invented by a

Re: radar history

2018-03-04 Thread William Donzelli via cctalk
> I dunno about these historical accounts. Radar tech history is a real minefield, and my advice is to take any historical accounts or studies that are older than ten or fifteen years old with a grain of salt. Often a big grain. "History is written by the victors" had been very strong with radar

Heathkit card cage with DEC cards available

2018-03-04 Thread Paul Anderson via cctalk
I recently found a Heathkit card cage ( 85-2001 121476 on backplane ) with a DEC M7270, M8044, M7946, and M8043. I still have a few Heathkit boards buried here sonewhere. Please contact me off list if you have any questions or wish to make an offer. Thanks, Paul

Re: FTGH: Pair of unknown extender cards

2018-03-04 Thread Fritz Mueller via cctalk
> On Mar 4, 2018, at 11:09 AM, Noel Chiappa via cctalk > wrote: > OK, another pair of unknown extender cards: Spring cleaning, Noel? :-)

FTGH: Pair of unknown extender cards

2018-03-04 Thread Noel Chiappa via cctalk
OK, another pair of unknown extender cards: http://ana-3.lcs.mit.edu/~jnc/tech/jpg/tmp/LargeExtender.jpg If anyone has a use for one or both, FTGH. They are 17"x10", and the support arms (nice touch) are about 3" long. No identifying marks that I can perceive, alas. The power leads are

Re: Some fun: who can identify this ?

2018-03-04 Thread Bob Rosenbloom via cctalk
On 3/4/2018 10:26 AM, Adrian Stoness via cctalk wrote: some sorta drawer doubht its a chad catcher with a hole for a handle as for what its from no idea On Sun, Mar 4, 2018 at 11:54 AM, Paul Koning via cctalk < cctalk@classiccmp.org> wrote: Chad catcher from a PC05 paper tape punch?

Re: Some fun: who can identify this ?

2018-03-04 Thread Paul Koning via cctalk
Chad catcher from a PC05 paper tape punch? paul > On Mar 4, 2018, at 12:40 PM, Pete Lancashire via cctalk > wrote: > > https://photos.app.goo.gl/ww7KPnPVexGJiqyE3

Some fun: who can identify this ?

2018-03-04 Thread Pete Lancashire via cctalk
https://photos.app.goo.gl/ww7KPnPVexGJiqyE3

Re: Re: Re: Re: radar history

2018-03-04 Thread Ed Sharpe via cctalk
that is precious! Ed#   In a message dated 3/4/2018 7:05:35 AM US Mountain Standard Time, d...@db.net writes:   On Sun, Mar 04, 2018 at 12:45:10PM -, Dave Wade via cctalk wrote: > > > > A very interesting story in this radar history is how the Dutch managed to > > rescue the EF50 tube,

Re: FTGH: Unknown extender card

2018-03-04 Thread Al Kossow via cctalk
It's too wide. On 3/4/18 4:40 AM, Noel Chiappa via cctalk wrote: > A couple of people have replied privately telling me it's for a Motorola > EXORbus/EXORciser. > > Noel >

Re: EF50 was Re: radar history

2018-03-04 Thread dwight via cctalk
The high frequency power tubes were required for better spacial resolution. My understanding was that major difference between the German radar and allied was that the Germans had a single trace, like a time domain reflectometer. The allies had a rotating image that is similar to what we see on

Re: EF50 was Re: radar history

2018-03-04 Thread Nico de Jong via cctalk
Oh sh..l., It was a bit too quick Apologies... /Nico - Original Message - From: "ANDY HOLT via cctalk" To: "General Discussion: On-Topic and Off-Topic Posts" Sent: Sunday, March 04, 2018 3:52 PM Subject: EF50 was Re: radar history >E =

Re: EF50 was Re: radar history

2018-03-04 Thread Nico de Jong via cctalk
.. also known as Noval base /Nico - Original Message - From: "ANDY HOLT via cctalk" To: "General Discussion: On-Topic and Off-Topic Posts" Sent: Sunday, March 04, 2018 3:52 PM Subject: EF50 was Re: radar history >E = 6.3v filament > F =

Re: FTGH: Unknown extender card

2018-03-04 Thread Jules Richardson via cctalk
On 03/03/2018 04:48 PM, Noel Chiappa via cctalk wrote: Hi, I'm not sure what kind of system this extender card I suppose there's a chance that it's for a piece of test equipment or something more analog in nature, and not computer at all - all sorts of equipment in the '60s had a

EF50 was Re: radar history

2018-03-04 Thread ANDY HOLT via cctalk
E = 6.3v filament F = Pentode 5x = B9G base Andy

Re: Re: Re: radar history

2018-03-04 Thread Diane Bruce via cctalk
On Sun, Mar 04, 2018 at 12:45:10PM -, Dave Wade via cctalk wrote: > > > > A very interesting story in this radar history is how the Dutch managed to > > rescue the EF50 tube, essential for these early radar receivers, to England > > just hours before the Germans invaded holland. I heard this

Re: FTGH: Unknown extender card

2018-03-04 Thread Robert via cctalk
On Sun, Mar 4, 2018 at 6:40 AM, Noel Chiappa via cctalk wrote: > A couple of people have replied privately telling me it's for a Motorola > EXORbus/EXORciser. Wasn't EXORbus keyed? I don't see a keyway in the photo. Robert

RE: Re: Re: radar history

2018-03-04 Thread Dave Wade via cctalk
> > A very interesting story in this radar history is how the Dutch managed to > rescue the EF50 tube, essential for these early radar receivers, to England > just hours before the Germans invaded holland. > > Read here ( not my site ): > > http://www.dos4ever.com/EF50/EF50.html#war > > Jos

Re: FTGH: Unknown extender card

2018-03-04 Thread Noel Chiappa via cctalk
> From: Brian Marstella > I have a CPU board with similar format that I bought thinking I'd > eventually figure it out. A couple of people have replied privately telling me it's for a Motorola EXORbus/EXORciser. Noel