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--- In ham_amplifiers@..., "Peter Voelpel" <df3kv@...>
wrote:

The chinese 8877 at 400 Euros seems to be a good choice,
a company nearby uses about 50 of those for two years without any

trouble

73
Peter

### How much is 400 Euro's in US dollars ?? Think it's at least
$600-$700.... + socket. $1400.00 for 2 of em.... not a
chance... no bargain there. A YC-243 is still a way better deal
at $1100- $1200.... and is the electrical eq of 6 x 8877's. The
YC-243 can also be rebuilt over and over.

## Have fun trying to play "matched pair" with 8877's.

later....... Jim VE7RF

-----Original Message-----
From: ham_amplifiers@...

[mailto:ham_amplifiers@...]

On Behalf Of 1800 Toll Free


The 8877 is a waste of money, for the dollars they choose to

demand for it.

For the price of a new 8877 you can purchase an 8170 and socket on

the used

/ pull market.

--- In ham_amplifiers@..., "Peter Voelpel" <df3kv@...>
wrote:

I guess the YC-243 is the same tube with a different socket

73
Peter

######### The YC-243 is a SOCKETLESS tube. They took a 3CX-
4500F3 industrial heater tube [looks identical to a 3x6.. except it
has no socket, is low mu and has a grid flange.. and lugs for fil]
and stuffed a hi mu grid in it.

### I have been teying to get through Eimac's head that sockets are
a pain in the ass... and are failure prone components... just ask
any broadcast engineer. The sveltlana 6000A7 is an excellent
tube.... u just won't be able to find anybody to rebuild one in the
USA.

### The socket for the 3x3 and 3x6 is now up to $375.00 from RF
parts [includes the grid ring]

### The EIMAC YC-243 sells for LESS than the EIMAC 3x6 .

### I posted a PDF I got from Eimac... on the YC-243...
under "files" on this site. It does have some minor errors in
it... which will get corrected.

### I paid $1100.00 for mine a few yrs back..... which is same
price as buying a 3CX-3000A7 + socket ... and way less than a 3x6 +
socket. In fact the YC-243 was less than the socketed Eimac 3x6.
Both the 3x6 and the YC-243 are an easy 9700 w CCS anode diss
too...... the sleeper of the year.

## Sockets are dead.. dead... toast, obsolete.

## Throw away tubes like 8877's are a joke. Even Ted Henry said
u gotta be nuts to buy one new. A new 3CX-3000A7 is exactly $50.00
more than a new 8877. [the 3x3 is rebuildable]...... which would
you want? A 3x3 with 50 w of drive will do 1500 w out.... and
200w of drive will give u 5200 w out... and very clean imd.

### The 3x6 and esp the YC-243 imo.. blow em all away. It's the
biggest bang for the buck bar none. None of the rebuider's have
ever seen a YC-243 with a blown out grid either.

### we are not gonna even discuss stuff like 3CX-800A7's or 3CPX-
800A7's.

## The russian 4CX-800A7's while cheap..for now... suck huge idle
current. Ask anybody with a QRO amp.... 450 ma zsac... and 675 ma
on the 3 x holer.

## If the engine under ur hood of ur car isn't big enough... get a
bigger one... don't stuff 3 x engines in there.

### Svetlana does make a 3000F7.. which has flex leads for the fil..
and also a flex lead for the grid. Fellows will toss the grid flex
lead... and replace with a vac cap flance or a 2 x piec clamping
block. Eimac still makes a 3CX-3000F7 as well.

## If Svetlana now makes a socketless 6000A7... that's news to me...
or a mis print. Where did u see it ??

Later... Jim VE7RF

-----Original Message-----
From: ham_amplifiers@...

[mailto:ham_amplifiers@...] On Behalf Of 1800 Toll Free

After having conversed with Jim over the last few days via email,

I'm

inclined to believe the new "tube of choice" is going to be the YC-

243...

It seems like the way to go.

Not to mention, the 11 meter market will probably sustain the

existance of the tube :) lol

--Toll_Free



On Wed, 17 Jan 2007 15:38:33 -0800, Peter Voelpel <df3kv@...>
wrote:

A reliable and not too expensive solution might be this version

of

3CX6000A7 by Svetlana:


"Better mechanical rigidity and long lasting concentricity of

the

filament is obtained from the improved mesh filament design

contributing

to a longer life. Flexible leads connect to the filament

terminals and a

flange is connected to the grid. The flange provides a

convenient way to

mount the tube."
Product ID: SKU15665

Price: ???594.94
including VAT 19% (???94.99)
[plus shipping]


Unfortunately not in stock at the moment
73
Peter


________________________________

From: ham_amplifiers@...
[mailto:ham_amplifiers@...] On Behalf Of Robert B.

Bonner

The trend is for cheap reliable power.

--



*Ratings are for transistors, tubes have guidelines*



Yahoo! Groups Links

The chinese 8877 at 400 Euros seems to be a good choice,
a company nearby uses about 50 of those for two years without any trouble

73
Peter

I guess the YC-243 is the same tube with a different socket

73
Peter

After having conversed with Jim over the last few days via email, I'm inclined to believe the new "tube of choice" is going to be the YC-243... It seems like the way to go.

Not to mention, the 11 meter market will probably sustain the existance of the tube :) lol




--Toll_Free

--



*Ratings are for transistors, tubes have guidelines*

The 8877 is a waste of money, for the dollars they choose to demand for it.



For the price of a new 8877 you can purchase an 8170 and socket on the used / pull market.


For about the same amount of money you can get all the parts.. Sure, your power xformer will cost a bit more for the anode voltage, but you will have a lot more life out of the tube / amp.



The glass tubes aren't being made anymore.... At least, not affordably. That means it's a waste of money / time to build around them.

It's a reflection of state of the art, or hollow state, if you will. the russian tubes are being used because they are cheap, not because of any big difference in technology.


This, of course, is just ramblings from some stupid CBer :)


--Toll_Free

--



*Ratings are for transistors, tubes have guidelines*

What bites is when the manufacturer purposely keeps it out of stock to make it look like it is a good thing and drive the price up.

BOB DD

Yeah Peter,

For some reason, the good stuff is never in stock.

BOB

A reliable and not too expensive solution might be this version of 3CX6000A7 by Svetlana:


"Better mechanical rigidity and long lasting concentricity of the filament is obtained from the improved mesh filament design contributing to a longer life. Flexible leads connect to the filament terminals and a flange is connected to the grid. The flange provides a convenient way to mount the tube."

Product ID: SKU15665

Price: €594.94
including VAT 19% (€94.99)
[plus shipping]


Unfortunately not in stock at the moment

73
Peter


________________________________

From: ham_amplifiers@... [mailto:ham_amplifiers@...] On Behalf Of Robert B. Bonner

The trend is for cheap reliable power.

The trend is for cheap reliable power. A couple 8877's will make moderate power at medium risk. A couple 3CX1200A7's will make almost as much power with low risk. Their limit to maximum power is its plate dissapation. Too bad Eimac didn't widely release the 1500 dissapation (YU whatever) version. It sounds like a great tube. No matter what a guy does. Whether it is a 6L6, 811A or an X2159 if you run it consurvatively with safeguards it will last forever. Push it and watch it go Bye-Bye. BOB DD
Sent From Mobile Device

[snip]

Seems to be alot of hams going to the GU84B tubes for their Big
amps over the 8877 or even the old 4-1000.

[snip]

I agree. Here's the breakdown:

The 8877 tube is hellishly expensive and
has a filament that is extremely sensitive
to shortened life because of a few hundredths
of an overvoltage. Additionally, its 25 watt
Grid Dissipation rating makes it vulnerable
if not sutably protected, to damage from
mistuning and arcs.

The 4-1000A being a Tetrode, is happiest being
Grid-Driven, but few amateurs have the inclination
to design and experiment with driving and neutralization
techniques, so many of these tubes end up Grounded Grid
at a miserable efficiency.

Additionally, the 4-1000A, with a 6KV at 1 Amp
anode requirement needs a power supply to suit, and
while transformers and diodes are plentiful, adequate
filter caps are not, and those that are available are
hellishly expensive once the array is gathered to
afford low ripple at maximum amperage.

Hal Mandel
W4HBM

Seems to be alot of hams going to the GU84B tubes for their Big
amps over the 8877 or even the old 4-1000.

--- In ham_amplifiers@..., FRANCIS CARCIA <carcia@...>
wrote:

Check the old RCA transmitting tube handbook showing how to apply RF

negative feedback to quad 811s

### The file I uploaded has nothing to do with 811's.

### W5CUL and myself wrote it last spring.[6 x months to write and
research it, and test everything] Although not directly related to
Amps.... not too many have seen it. And it was thought it may well
be interesting reading to some yaesu MK-V owner's. At least it's
squeaky clean after I got through with it.

### Hopefully my next PDF file depicting all the 3x6 schematics will
be as professional looking as the MK-V document. Stay tuned... it's a
time consuming, tedious process.

Later... Jim VE7RF

Check the old RCA transmitting tube handbook showing how to apply RF negative feedback to quad 811s

ham_amplifiers@... wrote:

Hello,

This email message is a notification to let you know that
a file has been uploaded to the Files area of the ham_amplifiers
group.

File : /mkvmods1_0.pdf
Uploaded by : pentalab <jim.thomson@...>
Description : Yaesu MK-V ESSB mod document

You can access this file at the URL:


To learn more about file sharing for your group, please visit:


Regards,

pentalab <jim.thomson@...>

1800 Toll Free wrote:

change a couple caps to make the harmonic-o-meter swing farther to the right, and call it 'your' design.

Wouldn't that be pronounced a "harmonica-meter" or "monicatometer" or"harmonomominer" on 11M?


One day, given some technological strides, with DSP the 11M op will be able
to completely remove the original signal, leaving only THD to swing the
Harmonc-o-meter.

If only the Old Man had known, he'd have designed a wouff hong just for
what would happen on what *used to be* our 11M band.

73,
Randy
KZ4RV

--- In ham_amplifiers@..., 1800 Toll Free
<TollFree1800@...> wrote:

It's something like this:



Voltage sampler, 1N series diode detector based 10Kw RMS meters.


Then, take the negative feedback off one side of a popular two

transistor

amp (2X2290, Texas Star DX250) and see > 500 watts PEP.

The 350 model (twin 2879s) will show near 1000 watts, PEP on

these

harmonicomoeters.

People actually do this, and put the B+ lead to the amp on some

type of

switch / solenoid... "Thing won't unkey, but hey, it's doin a
thousand!!!!!!.. I put this here foot switch in the positive lead

(read

this as old style headlight dimmer, footboard based) and use it to

unkey

the thing. Man, I never had a two pill doin a gran before!!!".


Make sense?

### why not just use a PEP reading wattmeter ?? Everybody and
their dog makes pep boards for the bird/CD wattmeter's. Those
depicted on the photo page are entirely HB.... 4 of em.. for all 4
x line sections.

### BTW.... Jay at Array Solutions now makes his new wattmeter with
couplers for 3-10-20 kw. They are extremely accurate........
unlike the bird [ 5% on average, 8% on pep] or the Coaxial
Dynamics wattmeter's [5% on average, 7% on pep]

### The trbl with both the bird /CD meter's is this... they are
ONLY +/- 5% of full scale... ANYWHERE ON THE SCALE !!

### IE: with a 1 kw slug.... and meter indicating say 100 w......
real power could be 50w... and meter is reading 50w too high [100
% error]...... OR.... real power could be 150 w.... and meter is
reading 100w.... or 50 W too low. [way off]

### ONLY time u get 5% accuracy is when meter is pegged. IE: 1
kw slug used.... indicates 1000 w. Real power could be 950w
or 1050 w.

### Point is this.... anything below full scale.. and accuracy
drops like a rock. ... so use the smallest slug u can get away
with.. for a given power level.

### The other problem with the bird/CD 7/8" line sections.. AND
also the 1 5/8" line sections is this. The 7/8" line sections are
use QC connectors.... which have this floozy small diam 1/8" pin
on the back end..... meanwhile, their is a 3/8" diam tube running
the entire length of the line section... dead center... inside the
7/8" ID tube. Remove the slug... and u can see the 3/8" tube
urself. The 3/8" tube will handle GLOBS of RF.... the QC
connector's won't.

### On the 1 5/8" line sections..... same deal.... except u need an
adaptor plate to use the QC connectors. same deal.... QC
connectors have this small 1/8" pin on back end.... embedded in
solid teflon cylinder. [same deal on 7/8" line sections]

### 11m ops tell me they can actually melt the teflon... runs out on
the table like molten candle wax !!

### U don't have that kind of mickey mouse on the array solutions
couplers.... trbl is... they gotta be ordered with one type of
connector only..... no big deal.... order em with 7-16 Dins...since
nobody is gonna run 15 kw with a SO-239 /Type N anyway.


### The Array solutions wattmeter's hold their 3% accuracy across
the spectrum. They are so fast... that just ONE.. "dit" sent at 60
WPM... will cause the digital numerical display to read... "14,250
w" The numerical display will hold it for how long u want... up to
2 seconds. You can do other cool stuff... with a PC... like graph
swr across the entire band, just by talking on ssb... and spinning
the dial. It will also show u stuff about ur xcvr u don't wanna
know... like typ overshoots.

### The Coaxial Dynamics 25 kw slug has each increment at 500
w... but u can easily visualize... and split into 250 w .

## The bird/cd may well have been the standard.... but imo... they
have now been well surpassed. The latest software for the array
solutions wattmeter's will indicate percentage of modulation for
AM broadcast use... or amateur use. Throw in the high swr shut
down... it's a total package.

Check it out.

later... Jim VE7RF

--Toll_Free

It's something like this:



Voltage sampler, 1N series diode detector based 10Kw RMS meters.


Then, take the negative feedback off one side of a popular two transistor amp (2X2290, Texas Star DX250) and see > 500 watts PEP.

The 350 model (twin 2879s) will show near 1000 watts, PEP on these harmonicomoeters.

People actually do this, and put the B+ lead to the amp on some type of switch / solenoid... "Thing won't unkey, but hey, it's doin a thousand!!!!!!.. I put this here foot switch in the positive lead (read this as old style headlight dimmer, footboard based) and use it to unkey the thing. Man, I never had a two pill doin a gran before!!!".


Make sense?


--Toll_Free

--



*Ratings are for transistors, tubes have guidelines*

I propose we have a new class of amplifier for the 11 meter crowd...

As it sits, we now have

A
AB1
AB2
B
C
etc.


Shouldn't somewhere, there be a class CB.....


:)



./End open can.of.worms



==Toll_Free

like a dispersive and compressive delay line in a radar system. What a cool idea run square wave and reconstruct. Class I amplifier (for idiot mode)

Harold Mandel wrote: