My Buddy still has my 4-1000A with a pair of BC610 plate transformers. It is stable 160 through 10. makes 1500 watts. makes a lot more with 5500 on the plate.
*/"Mike(W5UC) & Kathy(K5MWH)" <w5uc@...>/* wrote:
Jim, more years ago than I can remember I built a 4-1000A GG amp. It was ok, but hard to drive. At that time I had a HT-37. I came
upon a 3-1000Z, which can be plugged right into that same socket. With 75 watts from the HT-37 I could drive the 3-1000Z WAY beyond
legal limit on 80 meters, and it performed well up through 10
meters. It was stable and a very nice amp. I still wish I had not
sold it.
73,
Mike, W5UC
<>
The 4-1000A is a pain in the rear end and Im getting to old
to struggle with them.
73 Jim SM2EKM
-----------------
pentalab wrote:

>
> ### These YC-156's [and YC-172's] are a huge bang for the
> buck. 200 w drive = 10kw + out. No socket required. $400.00
>
> ### after messing about with multiple tube linears in the
>
> Later.... Jim VE7RF
>

I have several friends running the YC-156/179 GG, cathode driven with tuned input. With anode voltages of 5500 to 6500 they observe power gains upwards of 19 dB. As you reduce the plate voltage drive requirements go up but at the higher voltage, you can be VERY happy with less than 100 Watts drive.
The YC-156/179 is far better than the 4-1000 both in performance and cleanliness of signal (on air comparisons). Of course you can't watch the anode blush but the big gratification comes from other things ;)
73, Tony W4ZT
Jan Erik Holm wrote:

Jim,

Grid drive I suppose? In GG I would guess with 200W drive
maybe 5-6 kW, or?

Im planing to replace my 2x4-1000As with a YC-156, I think
its a ideal tube. As soon as I can get hold of a good one
at a decent price, would be a quick swap. However it will
be GG.

The 4-1000A is a pain in the rear end and Im getting to old
to struggle with them.

73 Jim SM2EKM
-----------------

pentalab wrote:

### These YC-156's [and YC-172's] are a huge bang for the buck. 200 w drive = 10kw + out. No socket required. $400.00
### after messing about with multiple tube linears in the
Later.... Jim VE7RF

Yahoo! Groups Links

Jan Erik Holm escribi:

Jim,

The 4-1000A is a pain in the rear end and Im getting to old
to struggle with them.

Why?.
Best regards
Guillermo - LU8EYW.

73 Jim SM2EKM
----------------

Jim,

Grid drive I suppose? In GG I would guess with 200W drive
maybe 5-6 kW, or?

I?m planing to replace my 2x4-1000A?s with a YC-156, I think
it?s a ideal tube. As soon as I can get hold of a good one
at a decent price, would be a quick swap. However it will
be GG.

The 4-1000A is a pain in the rear end and I?m getting to old
to struggle with them.

73 Jim SM2EKM
-----------------

pentalab wrote:

### These YC-156's [and YC-172's] are a huge bang for the
buck. 200 w drive = 10kw + out. No socket required. $400.00

### after messing about with multiple tube linears in the

Later.... Jim VE7RF

Jim, more years ago than I can remember I built a 4-1000A GG amp.? It was ok, but hard to drive. At that time I had a HT-37.? I came upon a 3-1000Z, which can be plugged right into that same socket.? With 75 watts from the HT-37 I could drive the 3-1000Z WAY beyond legal limit on 80 meters, and it performed well up through 10 meters.? It was stable and a very nice amp.? I still wish I had not sold it.

73,

Mike, W5UC

The 4-1000A is a pain in the rear end and Im getting to old
to struggle with them.

73 Jim SM2EKM
-----------------

pentalab wrote:

>
> ### These YC-156's [and YC-172's] are a huge bang for the
> buck. 200 w drive = 10kw + out. No socket required. $400.00
>
> ### after messing about with multiple tube linears in the
>
> Later.... Jim VE7RF
>

Guillermo,
Is the resistors in mention connected across the base and collector of each transistor? If so, someone could have been trying to add feedback to the transistors. Generally though a capacitor is in series with the resistor and the resistor-capacitor is connected across each collector and base. The cap blocks the DC at the collector from going to the base. If it had a +DC voltage from the collector going to the base, you would most assuredly have some burnt out transistors.
The RF input attenuator in that amp is probably made with resistors too. Is it possible it could be these?
Best,
Will
--- In ham_amplifiers@..., GGLL <nagato@...> wrote:

I'm searching for a solid state amplifier circuit, a Henry model

C130A30 (for

VHF FM). The one I have seems to have been modified, I see some

resistors

strangely connected both at base and collector; also after an

extensive search

(Google, Alltheweb, data sheet pages, and so) I did not yet found

nearly a

bare specification of the transistor used. Input is specified in the

range of

20..40 Watts, and output of 130 Watts, and as I see it, the circuit

consists

of a resistive input attenuator, then follows a first stage with a

CD-4778,

which drives three CD-4778 (yes, the same) in parallel. All four are

B-E open.

It has a nice LPF at the output. Very good components with the

exception of

the above stated resistors.

Thanks in advance

Best regards
Guillermo - LU8EYW.

Yahoo! Groups Links

I have obtained a Drake L7 amp from an estate. It had lightning
damage to the power supply. I need to replace a couple capacitors and
diodes. Has anyone rebuilt this supply? I read somewhere on the Net
that a complete board can be purchased from a company in California
but I lost the info. Any suggestions?
Tom W8JWN

### These YC-156's [and YC-172's] are a huge bang for the buck. 200 w drive = 10kw + out. No socket required. $400.00 ### after messing about with multiple tube linears in the Later.... Jim VE7RF

On Sep 21, 2006, at 12:24 AM, Jan Erik Holm wrote:

Bill Fisher W4AN committed suicide on April 4 2004.
You can read here:

Thanks, Jim. Was the story about him dying in a car crash true or just a coverup?

73 Jim SM2EKM
--------------------------------------------------------------

R L Measures wrote:

W4AN was not a fan of free speech -

RE: W4AN & free speech: After Bill Fisher died at such a young age,
I tried to find out how it happened. I could find out nothing from
the County Coroner. Rumor was that there was an automobile accident,
that the car landed in water a considerable distance from the
highway, and that it happened near a drag-strip in Georgia. My guess
is that the Coroner's Report was suppressed because the toxicology
finding would have been an embarrassment.

he replaced me as Admin of
Towertalk when I refused to censor posts there; this is not a knock on
Bill, just a difference of philosophy.

Since Eimac never made a chimney for either a 3CX-3000A7 or a 3CX-6000A7 [or the socket] several after market chimneys have appeared. I purchased the one for the 6000A7. It was solid 1/4" thick teflon... straight up and down, no flanges.... and it's weight held it to the chassis. 6.130" ID 6.630" OD We found that this restricted the airflow up from the chassis too much. [both the ceramic 'stem' on the 3000/6000 are identical.. and much smaller diam than a YC-156 or a 10,000A7. ] For an experiment, I remember W7IUV had fabricated a fiberglass box around his YC-156.. for a chimney. We tried the same trick... except the vertical sidewalls were made from wood... about 9" square... top was also made from wood.... and the original chimney was placed in a groove.. on top of this wooden affair. Now we could increase the hole sizes on the chassis. The result was a huge improvement! Intead of the original 205 cfm... we are now getting an easy 320 cfm [using a Dayton 5C508 dual speed, capacitor start blower].
On the next chimney... we will toss the after market straight up and down chimney... and just increase the vertical sides of the box... and use a solid teflon top lid.. with a 6.130" hole in it. This technique can be used on any metal tube. The after market chimney's for the 3000A7 [4.130" ID] restrict the air too much as well. On one 3000A7 project... I used a SK-
306.. designed for a 4CX-5000A7.. which is a bit too big a diam at the top.... so we filled the gap.. by wrapping a few layers of silicone rubber around the tube.. held in place by a SS hose clamp... worked good. ... since the SK-306 chimney has a flared out base. Eimac specs the 6000A7 for 205 cfm of air. [based on a 50 deg C /121 deg F inlet air temp.] With 320+ cfm... and an inlet air temp of 25 deg C..... we calculated the anode diss is now an easy 8500+ Watts !
Talk about the sleeper of the year. This tube is real easy to increase it's stock anode dissipation. The secret is the small diam ceramic 'stem',makes for larger fins underneath... compared to a say 5000A7/YC-156..... which has a huge diam 'stem'... and a smaller anode cooler. The Dayton 5C508 blower is a dual speed 1100 rpm /1450 rpm unit. Comes with a single oil filled start cap. The over temp protected motor is partially embedded in one end. It draws intake air from both ends. With no back pressure... in free air, it's 765 cfm on high speed..... and down to 320 cfm @ .9" water pressure. They installed clip weights to some of the impellor blades.... so it's perfectly balanced from the factory... like balancing a car wheel.
Later..... Jim VE7RF

Jim,
What you describe may help a little. The problem is the internal connection from the ring to the grid itself, and it's size. If it's only a piece of wire, you may not gain anything as the wire would be the bottleneck I would think. The ring would help a little by being a larger heatsink for the connection itself, but the grid itself is still wire which it's size and coating (gold, etc) can only take so much current. The ring would have to dissapate the heat from the grid via the internal connection(s).
Best,
Will

From: ham_amplifiers@... [mailto:ham_amplifiers@yahoogroups.

com]

On Behalf Of pentalab
Sent: Donnerstag, 21. September 2006 22:12
To: ham_amplifiers@...
Subject: [ham_amplifiers] Re: Can Grid Dissipation in metal GG triodes be
increased ????



--- In ham_amplifiers@ <mailto:ham_amplifiers%40yahoogroups.com>
yahoogroups.com, "pentalab" <jim.thomson@> wrote:

Gents

On these 3CX-6000's and also the socketless version [ YC-

243],

I fool with from time to time, Eimac/ Svetlana state's the

grid

diss at 225 Watts CCS. [3CX-3000A7 is also 225 w CCS grid]

Now, since the tube(s) can be operated in either GG OR grid driven.... it occured to me that in grid driven mode... the grid should still has a 225 w CCS rating ???
The point here is..... in GG service... you bolt this huge grid ring to the chassis.... and in the case of the socketless version.... an even bigger diam grid flange is bolted to the chassis !
Now... that alone should heatsink the grid ??? Since the

grid

is sitting in a vac... the only way for thermal heat to escape is via the grid flange.

Since the below chassis compartment is pressurized... one might think the actual grid dissipation can perhaps be increased

via

this heatsink action ?? [GG mode]
Am I out to lunch here ???
Later..... Jim VE7RF

### Did anybody actually read the above ???
Later.... Jim VE7RF