Antonio Vernucci wrote in message
...
Noone has raised the issue of how long 6JB6s last.

If they are used with caution they last for a long time, but if one tries to
squeeze the last watt out of them (and the 6JB6s invite you to do so, thanks
to their strong cathode emission) they can last for a VERY short time.

The 6146 have a lower cathode emission and do not then lend themsleves to be
squeezed so badly as the 6JB6s. So there is less harm to inadvertently
destroy them.

To my experience the Sylvania 6JB6s (those sold by Drake as spares) perform
better than the GE 6JB6s, and are are easier to neutralize. The RCA 6JB6s,
luckily much less common, were no good.

73

Tony, I0JX

Absolutely Tony... I share the same experiences as you. I've recently
listened to the youngsters getting their hands on the Drakes but not knowing
how to tune the pi-network with the consequence that they destroy the 6JB6's
in short order---and having to put out $100 for another set. Those sweep
tubes weren't very forgiving... If I remember, we never really worried
about hurting the 6146's as they seemed to keep on working. Furthermore,
correct me if I am wrong, I don't think we ever considered having matched
6146's like we did with the sweep tubes.

RG

Okay, you've convinced me. Drake had no idea what they were doing.

73,
Darrell, WA5VGO







"RadioGuy" wrote in
:


Michael A. Terrell wrote in message
...
Darrell wrote:

You miss the point. Drake didn't buy their tubes from the surplus
market.
They bought them bulk packaged from the manufacturer. It did make
sence from their standpoint and it didn't compromise the product.
From a boatanchor standpoint I wish they had used 6146's. But when
put in their shoes in 1963, it was a good business decision.

Most horizontal output tubes have distortion products comparable to
the 6146 if you keep the voltage and power down to reasonable
levels. Third order products are typically in the -25 Db range
which is right in there with the 6146.

73,
Darrell, WA5VGO


Another point of view: If a ham needed new final tubes he could
buy
them at any TV shop or parts house, but the 6146 wasn't always
available over the counter without a wait.

--
?

Michael A. Terrell
Central Florida

Well... maybe if you were using a single tube that would be the case.
The Drake gear (besides gear from other manufacturers) used more than
one tube requiring them to be matched. I recall Drake sold matched
sets of tubes after checking their cathode currents in a test fixture.
The tubes were them marked and collected into sets for sale. I
recall seeing the number '18' on the envelope of a matched set of
6JB6's. What '18' meant I just don't know. I also recall some folks
back then claim the the tubes were also matched on the basis of plate
capacitance. I'd look at the matched sets that I have but they have
been in sealed packages for nearly 30 years so I hate to open them.

The 6146's weren't a problem... we always seemed to get them if we
needed them---they seemed to be everywhere. They were sort of like
antenna insulators---if you needed them someone had them and would
give them to you. I never bought a 6146... One fellow gave me a
couple of boxes of 6146W's (yea... they were in the white boxe with
the black print on the side ;-). A lot of manufacturers were using
the 6146's in their designs and the tubes had been around a long
time---for decades.

RG

I agree. There is little, IF ANY, correlation between the "consumer" price
of components and the commercial (manufacturers') pricing. Besides the
quantity discount, there are other factors: One is that Drake may have, and
probably did, buy other tube types from the same supplier (which may not
have been the tube manufacturer!) That can leverage prices downward on one,
a few, or all types. Other components come into play too, for different
tube types may not use the same sockets, and may require different designs
for stability, etc so that a particular tube might require, say, a more
expensive bypass capacitor (just an example). Then there might have been
power supply consideratons involving the different voltages/currents for the
different types. These decisions are made in the early stages of design,
and usually revolve around what is the cheapest way to achieve the desired
result. Even if, at a later date, experience factors dictate using a
different tube, I doubt that (in this discussion case) the cost/benefit
tradeoff would favor going to the 6146. In order to know whether Drake was
smart, we need to know all the decision factors and conditions at the time.
Of course, hindsight always has 20-20 vision.

In the good OLD tradition of Hamming, those who so desired could do their
own engineering redesign. Yank out the sweeps and associated
circuitry/components if you didn't like 'em and build out with 6146s.

73,
Dube K4DWW






"RadioGuy" wrote in message
...

Antonio Vernucci wrote in message
...
I don't recall the 6146 was that expensive. We could find them at the
hamfest, surplus and they were routinely given away from one ham to
another... heck,

What you say is true for a ham in need of just replacing a pair of tubes.
But it would not have been true at all for Drake.

A company producing ham gear cannot depend on tubes found at a good price
here and there. They have to place a contract with a tube manufacturer who
can guarantee delivery in time and in the required quantities. Prices are
then market prices, not surplus prices.

73

Antonio I0JX

Well, the tube (6146) was in constant production during Drakes operation
(about 30 years) so it would imply that they were very common and
cheap---practically every other amateur equipment manufacturer was using
the
6146. Large numbers were used by the military and commercial services.
My
gosh... if Heath was using them they certaintly couldn't have been that
prohibitive to design with. So it begs the question why Drake was using
them.

RG

Its very simple. POWER sells. Sweep tubes have that extra output for the
bigger price tag. A $9.00 sweep tube in the 70's cost a dealer $3.00. Cant
imagine what the low cost would be to a manufacturer. Bottom line for all
companies......PROFIT.......PROFIT........PROFIT.

--
Regards,
Gary...
"RadioGuy" wrote in message
...
The thought came to me the other day whle thinking about the cost of
6JB6's
nearly $100 for a set; I paid $18.00 for a matched set of three at AES
back
in the 1970's and I got plenty of spares. Why did Drake use those cheap
ass
sweep tubes in their final instead of the old standard 6146 to begin with?

Sure, back then it seemed in vogue to use sweep tubes in amateur gear
(yea,
sure, Swan gear...) but as I recall, we thought that Drake was kinda
cheesy
to use those tubes anyway. I gonna stick my neck out and say Drake
engineering wasn't the end all that the youngsters think nowadays.

(Yes... I have a complete Drake station (including amplifier)---the whole
line-up in pristine, vitrually unused condition in crisp factory cartons
including accessories, catalogs and a handful of the right-angle
Switchcraft
microphone (black cap) and key (red cap) plugs that Drake originally
supplied not that PL-whatever. Original owner---me---so it's not sour
grapes.)

RG

"RadioGuy" wrote in message
...
The thought came to me the other day whle thinking about the cost of
6JB6's
nearly $100 for a set; I paid $18.00 for a matched set of three at AES
back
in the 1970's and I got plenty of spares. Why did Drake use those cheap
ass
sweep tubes in their final instead of the old standard 6146 to begin with?

Sure, back then it seemed in vogue to use sweep tubes in amateur gear
(yea,
sure, Swan gear...) but as I recall, we thought that Drake was kinda
cheesy
to use those tubes anyway. I gonna stick my neck out and say Drake
engineering wasn't the end all that the youngsters think nowadays.

(Yes... I have a complete Drake station (including amplifier)---the whole
line-up in pristine, vitrually unused condition in crisp factory cartons
including accessories, catalogs and a handful of the right-angle
Switchcraft
microphone (black cap) and key (red cap) plugs that Drake originally
supplied not that PL-whatever. Original owner---me---so it's not sour
grapes.)

RG


When the Drake vacuum tubes rigs were designed, the sweep tubes were being
mass produced for the TV market and WERE very cheap.

However, there may have been another reason.
If I remember correctly, the advertised power output of the TR3/TR4 and the
T4X, etc was higher than the 180 watts input/100 watts output that was
typical from a pair of 6146's. A pair or trio of sweep tubes is capable of
a much high PEP rating than is a pair of 6146's - albeit maybe not for
long....


Thus there was a marketing race at the time.
Each manufacturer was claiming higher and higher power levels for their
"bareful" rigs.
Swan was surely the champ with that - claiming up to 700 watts input and
about 500 watts output for some of their rigs.
Drake didn't go so far but probably still wanted to claim more power than
the 180 watts input/100 watts output of Collins and Heathkit.

National also used sweep tubes in their transceivers. For example, they used
the 6GJ5 in their NCX-3 and the NCX-5 and at first were conservative with
their rating, also claiming just 180 watts in/about 100 watts out. Later
they joined the PEP race with their NCX-500, etc.

Thus part of the answer may simply be marketing.

73,

Doug/WA1TUT

You mentioned that Heathkit used 6146's in virtually all of their
gear. That is a valid statement, but they used 6GE5 sweep tubes in
the lower price-point HW-series monobanders, including the ones for
MARS/CAP. It was a purely a matter of economics, I think. Retail
price aside, there had to have been more manufacturing volume on the
sweep tubes, because just about every family had a TV set.

I now have a 4B-line, and also a bunch of HW-series rigs. The 6GE5's
are fairly inexpensive even today, compared to 6146A's or W's or the
later GE 6146B's that Heathikit blessed.

73,
Ted KX4OM

On Thu, 24 Mar 2005 00:37:15 GMT, "RadioGuy"
wrote:


Antonio Vernucci wrote in message
...
I don't recall the 6146 was that expensive. We could find them at the
hamfest, surplus and they were routinely given away from one ham to
another... heck,

What you say is true for a ham in need of just replacing a pair of tubes.
But it would not have been true at all for Drake.

A company producing ham gear cannot depend on tubes found at a good price
here and there. They have to place a contract with a tube manufacturer who
can guarantee delivery in time and in the required quantities. Prices are
then market prices, not surplus prices.

73

Antonio I0JX

Well, the tube (6146) was in constant production during Drakes operation
(about 30 years) so it would imply that they were very common and
cheap---practically every other amateur equipment manufacturer was using the
6146. Large numbers were used by the military and commercial services. My
gosh... if Heath was using them they certaintly couldn't have been that
prohibitive to design with. So it begs the question why Drake was using
them.

RG

Ted Bruce wrote in message
...
You mentioned that Heathkit used 6146's in virtually all of their
gear. That is a valid statement, but they used 6GE5 sweep tubes in
the lower price-point HW-series monobanders, including the ones for
MARS/CAP. It was a purely a matter of economics, I think. Retail
price aside, there had to have been more manufacturing volume on the
sweep tubes, because just about every family had a TV set.

I now have a 4B-line, and also a bunch of HW-series rigs. The 6GE5's
are fairly inexpensive even today, compared to 6146A's or W's or the
later GE 6146B's that Heathikit blessed.

73,
Ted KX4OM

Yup... for sure... I forgot about those monobanders. I even had one
myself---the HW-32A.

Well, you raise the question that's been on my mind for quite awhile---just
what was the production on the 6146? I don't have the slightest idea how to
find that tidbit. They were well in production before TV became
commonplace---maybe 10 years or so. Just what was the production figure on
the 6JB6? To be honest the 6JB6 doesn't sound like a common tube. I recall
the horizontal deflection amplifier tubes like the 6DQ5 and 6DQ6 but looking
in my 1961 RCA tube handbook I don't seen the 6JB6 listed.

I recall, Kenwood had 6146's in their TS-520, correct me if I'm wrong but
wasn't it a 6146 of Japanese production ( I remember they had the shiny
chrome finish on the metal surfaces that typified some of the Japanese
parts)?

RG

DOUGLAS wrote in message
k.net...

"RadioGuy" wrote in message
...
The thought came to me the other day whle thinking about the cost of
6JB6's
nearly $100 for a set; I paid $18.00 for a matched set of three at AES
back
in the 1970's and I got plenty of spares. Why did Drake use those cheap
ass
sweep tubes in their final instead of the old standard 6146 to begin
with?

Sure, back then it seemed in vogue to use sweep tubes in amateur gear
(yea,
sure, Swan gear...) but as I recall, we thought that Drake was kinda
cheesy
to use those tubes anyway. I gonna stick my neck out and say Drake
engineering wasn't the end all that the youngsters think nowadays.

(Yes... I have a complete Drake station (including amplifier)---the
whole
line-up in pristine, vitrually unused condition in crisp factory cartons
including accessories, catalogs and a handful of the right-angle
Switchcraft
microphone (black cap) and key (red cap) plugs that Drake originally
supplied not that PL-whatever. Original owner---me---so it's not sour
grapes.)

RG


When the Drake vacuum tubes rigs were designed, the sweep tubes were being
mass produced for the TV market and WERE very cheap.

However, there may have been another reason.
If I remember correctly, the advertised power output of the TR3/TR4 and
the
T4X, etc was higher than the 180 watts input/100 watts output that was
typical from a pair of 6146's. A pair or trio of sweep tubes is capable
of
a much high PEP rating than is a pair of 6146's - albeit maybe not for
long....


Thus there was a marketing race at the time.
Each manufacturer was claiming higher and higher power levels for their
"bareful" rigs.
Swan was surely the champ with that - claiming up to 700 watts input and
about 500 watts output for some of their rigs.
Drake didn't go so far but probably still wanted to claim more power than
the 180 watts input/100 watts output of Collins and Heathkit.

National also used sweep tubes in their transceivers. For example, they
used
the 6GJ5 in their NCX-3 and the NCX-5 and at first were conservative with
their rating, also claiming just 180 watts in/about 100 watts out. Later
they joined the PEP race with their NCX-500, etc.

Thus part of the answer may simply be marketing.

73,

Doug/WA1TUT

Well said Doug... I forgot about that---there was a power race back in the
70's. Some of us did get 'big eyes' when Swan came out with the 500. And
now that you mentioned it, I remember some of us looking at the Drake's 300
watt (input) tranceiver as a selling point ( I think the power race ended
somewhat with the advent of solidstate and the fairly uniform 100 watt
specification).

Drake had a problem meeting their power claim later for the TR-4C/CW/CW+RIT
(I don't know about the older models), resulting from the changes to FCC
regs regarding spectral purity (97.73). Drake had a notice that the final
could not be loaded to more that 350 ma. so as to remain within the new
spec. The older tune-up procedure reached maximum output with a plate
current of 380 to 500 ma. I am not going to venture to say if the 6JB6's
had anything to do with having to go to a reduced output as opposed to using
the 6146's in their place regarding spectral purity but I sure would like to
hear comments on this point.

I like the note in the operators manual regarding tune-up:

3-7. TUNE UP. Do not allow plate current to exceed 0.1 Amperes for more
that 6 seconds with the PLATE control not tuned for minimum plate current or
maximum output.

CAUTION Failure to observe the warning above will result in rapid final
amplifier tube deterioration due to excessive plate dissipation.

RG

Hi, Gang

The 6146 was introduced by RCA in Jan 1952 QST (full page ad).
It was advertised as the big brother to the 2E26, which had been around
since about 1946.

73,
Ed Knobloch


RadioGuy wrote:
Well, you raise the question that's been on my mind for quite
awhile---just
what was the production on the 6146? I don't have the slightest idea how to
find that tidbit. They were well in production before TV became
commonplace---maybe 10 years or so.

RadioGuy wrote:
Well, you raise the question that's been on my mind for quite
awhile---just
what was the production on the 6146? I don't have the slightest idea how
to
find that tidbit. They were well in production before TV became
commonplace---maybe 10 years or so.

Well here is how you find stuff

Go to this URL:
http://www.google.com/

Type in 6146 vacuum tube (Web Search)
Get several responses -- weed thru them
In the second down is Issue 6 Articles
which sez
the type 6146, was new in 1952.

Wanna see a photo of a 6146
Use google and search images for 6146
Wanna see a pinout
use google and search images for 6146 vacuum tube


Please make a note of it. Google that is -- can find damn near anything.
Including you -- see search groups

--
CL -- I doubt, therefore I might be !