I hope this is not a double post, but I've waited 8 hours and have seen
nothing.

Fred mentioned on his first post that the dynamotors had been removed
from his two 18S units.
When I saw illustrations in this instruction manual, the first thing I
saw in a top view of the unit were the 811's and mod transformer. They
certainly appear to be lifted from an ART-13 as well.

It's been a long time ago, but my father told me about the 18S receiver
and the fact that only 28 volts were used on the plates and screens. I
was just a kid of 9 or 10 years old. Even back then I knew that most
radios needed a hundred volts or so. Even the "All American Five"
series string AC/DC sets had better than 100 volts B+.

John

In Fred's first post, he mentioned that the dynamotors had been
removed.

When I first looked at a topside view of the 18S in the instruction
book, the 811's and mod transformer sure look like they came from an
ART-13 as well.

John

Fred did mention in his first post that the dynamotors had been removed
from his two units.

When I saw the pictures of the 18S in this instruction manual, I
immediately noticed the 811's and mod transformer. They look as if they
were lifted from an ART-13 as well.

John

That's absolutely correct. They (Collins) used as much of the existing
ART-13 parts, it appears, as possible. Seems like the thing to do,
given the design task at hand. Its just too bad they designed it with
plug-in components. At the time, though, 20 channels was quite
sufficient the HF aeronautical service. And, if you ever see one of the
ART-13's with the Comco crystal oscillator in it, that was the original
attempt to get a satisfactory rig for both the military and the
airlines. I've tried to find out how many years the ART-13 was use by
the airlines, but no joy. When I worked for Page Airways FBO (DCA) in
the mid-60's, they had the books for the Comco ART-13A and the souped-up
ARC-1 VHF set. It appears that the ART-13 was considered unusable
somewhere about 1955, although my ATC came from Moffed Field and had a
NASA channelization chart with a 60's date on it. I still notice ads in
50's and early 60's QSTs for the surplus dealers trying to buy-up
ART-13s and BC-348s. Maybe for the 3rd world? Maybe NASA pushed the
date on mine?? Probably why it still works so well...hi!!!

Litzendraht wrote:
I can't seem to post on Google, so I'll try it here on Talkabout.

Fred mentioned in his first post that the dynamotors had been removed from
both of his units.

When I looked at the pictures in this 18S instruction manual, the first
thing I noticed were the 811's and mod transformer. They look like they
were lifted from an ART-13 as well.

John

Jeep,
I too recall the adds in QST and CQ from commercial companies
looking for 348's and ART-13's. I always figured that stuff was
destined for South America. Also, I knew an old timer that worked for
an exploration division of Magnolia Petroleum, and he worked with
BC-312's and 348's and even a Hallicrafters HT-9 transmitter. All of
this stuff was really considered obsolete in the early Sixties, but I
guess it proved reliable and was used for some form of field
communications.
I mentioned earlier that my father was a field engineer for Collins
from '52 to '55 and worked with the 18S and 180L tuner. I was a kid
back then 8 or 10 years old, and I still remember being intrigued with
the 18S receiver when he told me it had no B+ supply, but used 28 volts
for plate voltage.
John

I can't seem to post on Google, so I'll try it here on Talkabout.

Fred mentioned in his first post that the dynamotors had been removed from
both of his units.

When I looked at the pictures in this 18S instruction manual, the first
thing I noticed were the 811's and mod transformer. They look like they
were lifted from an ART-13 as well.

John