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Re: HIGH SWR / HIGH REFLECTED POWER SHUT DOWN CIRCUIT !!

PA3DUV
 

¿ªÔÆÌåÓý

Great info Jim!
NOW we're talking amplifiers ;-)
?
Thuis yahoo group has the possibility of posting pictures, files?and the like. Some pics of your "QRP" amps? (They also make the usual? 10 kw?? 5 kw.. 2.5 kw?? qrp? slugs.) would be very much appreciated.
?
Thanks again for the very interesting contributions!
?
Cheers, Dick
PA3DUV
?

----- Original Message -----
From: pentalab
Sent: Saturday, September 23, 2006 8:53 AM
Subject: [ham_amplifiers] HIGH SWR / HIGH REFLECTED POWER SHUT DOWN CIRCUIT !!

--- In ham_amplifiers@yahoogroups.com, "Peter Voelpel"
wrote:
>
> Hi Jim,
>> I prefer that my GG amps cannot run in too high dissipation at
full
> drive. They should have no problem when the antenna gets lost...
>
> 73
> Peter

### Peter, et all

### I had an engineer buddy of mine cook up a high reflected
power shut down circuit for me. My buddy got a hold of a
ton of Bird single line sections. He joined two of em
together with some brass rod and soldered the outside flanges...
to fabricate a "double line section".

### He made two such assemblies. We installed one on the
input of the amp... and the 2nd one on the output. [4 x slugs
installed]

### Since the big amp is remoted 30' away from the shack.....
we had to be able to read all 4 x line sections in BOTH
locations. My engineer buddy designed a peak reading board that
would work with all 4 x line sections.... and continuously
monitor the PEP reflected power from the ant [line section # 4 ]

### Only one bird 30 ua meter is used in each location.... and
either end can be switched independently to any of the 4 x
line sections. He used line drivers at the amp end.. to drive
the box in the shack.

### The high PEP reflected power threshold is fully
adjustable... and in this case was set to 1 kw. When the
threshold is exceeded.... a minature dpdt relay operates [ in <2
msecs] and one set of contacts applies -10 vdc to the ALC
jack of the Yaesu MK-V.... shutting it down asap !!

### The 2nd set of conatcts activates a 2nd, identical relay
[also in < 2 msecs]

### This 2nd DPDT relay opens up the key line to both the IPA
[ intermediate pwr amp] and also the 12 kw amp. The
circuit latches.... and lights a red led. A spring loaded
push button resets the circuit . [AFTER you find out why the
high swr condition occured]

### Since the 2 x minature relay's are sequenced.... the ALC
shut down on the xcvr occurs 1st.... followed by kicking BOTH
amps off line ! NO Hot switching!

### To key both amps.... I used a PAIR of P+B opto
isolators.... they run on +13.8 vdc @ 10 ma each.
The "electronic TX ground" from pin 2 of the MK-V's band
data jack supplies the grnd to both opto's on TX.

### The output side of each opto is rated at 200 Vdc @ 1 A
CCS. They also have 4 kv isolation between input and output...
and operate in under 100 microseconds. Cheap too.

### We used +120 vdc to operate all 4 x vac relays in the big
amp. [speed up circuit, with a pair of dropping resistors]

### The high swr circuit could have been configured to open
off the INPUT to both opto's instead.. of the Opto outputs. Moot
point.

## I had my engineer buddy also include a short 12-14 msec
delay... used in conjunction with the yaesu "TX inhibit lead"
[used on both the 1000-D... plane MP.... MK-V /field.

## BOTH amps are keyed NOW.... after 10-14 msecs... TX
inhibit is removed... allowing full power from the Yaesu MK-V.

### This delay ensures the vac relays won't hotswitch on TX...
even though all 4 x are sped up.... we are using RJ1A's on the
input side [one for drive RF... the 2nd RJ1A shorts out the
100k resistor to remove the cutoff bias. We paralled a pair
of larger, slower vac relays on the output 10 kw side.

### We didn't want a situation where input relays operated
1st... drive applied to cathode... and no ant connected ...yet !!

### This delay circuit is for SSB / FM /AM

### In the MK-V menu.... on CW only.,... you can delay the RF
by 0-30 msecs [ digital delay... NOTHING gets truncated
either] ... and still key the amps in real time... NOW. It
needs to be set between 10-30 msecs.

## The above T/R scheme is super fast vox cw/ ssb /fm /am.
Due to the 'slower' larger vac relays on the 12 kw output
side....qsk is not recomended.

### If anybody is interested.... the high swr circuit will be
made available down the road... along with the rest of the
schematics. It's saved everyones bacon a few times so far...
works slick... and works on any bird line section / slug size.

Later......... Jim VE7RF
HIGH SWR / HIGH REFLECTED POWER SHUT DOWN CIRCUIT !!

pentalab
 

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

Hi Jim,
I prefer that my GG amps cannot run in too high dissipation at
full
drive. They should have no problem when the antenna gets lost...

73
Peter
### Peter, et all

### I had an engineer buddy of mine cook up a high reflected
power shut down circuit for me. My buddy got a hold of a
ton of Bird single line sections. He joined two of em
together with some brass rod and soldered the outside flanges...
to fabricate a "double line section".

### He made two such assemblies. We installed one on the
input of the amp... and the 2nd one on the output. [4 x slugs
installed]

### Since the big amp is remoted 30' away from the shack.....
we had to be able to read all 4 x line sections in BOTH
locations. My engineer buddy designed a peak reading board that
would work with all 4 x line sections.... and continuously
monitor the PEP reflected power from the ant [line section # 4 ]

### Only one bird 30 ua meter is used in each location.... and
either end can be switched independently to any of the 4 x
line sections. He used line drivers at the amp end.. to drive
the box in the shack.

### The high PEP reflected power threshold is fully
adjustable... and in this case was set to 1 kw. When the
threshold is exceeded.... a minature dpdt relay operates [ in <2
msecs] and one set of contacts applies -10 vdc to the ALC
jack of the Yaesu MK-V.... shutting it down asap !!

### The 2nd set of conatcts activates a 2nd, identical relay
[also in < 2 msecs]

### This 2nd DPDT relay opens up the key line to both the IPA
[ intermediate pwr amp] and also the 12 kw amp. The
circuit latches.... and lights a red led. A spring loaded
push button resets the circuit . [AFTER you find out why the
high swr condition occured]

### Since the 2 x minature relay's are sequenced.... the ALC
shut down on the xcvr occurs 1st.... followed by kicking BOTH
amps off line ! NO Hot switching!

### To key both amps.... I used a PAIR of P+B opto
isolators.... they run on +13.8 vdc @ 10 ma each.
The "electronic TX ground" from pin 2 of the MK-V's band
data jack supplies the grnd to both opto's on TX.

### The output side of each opto is rated at 200 Vdc @ 1 A
CCS. They also have 4 kv isolation between input and output...
and operate in under 100 microseconds. Cheap too.

### We used +120 vdc to operate all 4 x vac relays in the big
amp. [speed up circuit, with a pair of dropping resistors]

### The high swr circuit could have been configured to open
off the INPUT to both opto's instead.. of the Opto outputs. Moot
point.

## I had my engineer buddy also include a short 12-14 msec
delay... used in conjunction with the yaesu "TX inhibit lead"
[used on both the 1000-D... plane MP.... MK-V /field.

## BOTH amps are keyed NOW.... after 10-14 msecs... TX
inhibit is removed... allowing full power from the Yaesu MK-V.

### This delay ensures the vac relays won't hotswitch on TX...
even though all 4 x are sped up.... we are using RJ1A's on the
input side [one for drive RF... the 2nd RJ1A shorts out the
100k resistor to remove the cutoff bias. We paralled a pair
of larger, slower vac relays on the output 10 kw side.

### We didn't want a situation where input relays operated
1st... drive applied to cathode... and no ant connected ...yet !!

### This delay circuit is for SSB / FM /AM

### In the MK-V menu.... on CW only.,... you can delay the RF
by 0-30 msecs [ digital delay... NOTHING gets truncated
either] ... and still key the amps in real time... NOW. It
needs to be set between 10-30 msecs.

## The above T/R scheme is super fast vox cw/ ssb /fm /am.
Due to the 'slower' larger vac relays on the 12 kw output
side....qsk is not recomended.

### If anybody is interested.... the high swr circuit will be
made available down the road... along with the rest of the
schematics. It's saved everyones bacon a few times so far...
works slick... and works on any bird line section / slug size.

Later......... Jim VE7RF
Coaxial Dynamics now makes a 25 kw slug for a 7/8" line section !!

pentalab
 

Gents

This may well be old news to some... but Coaxial Dynamics makes
a 25 kw slug.[2-30 mhz].. for a standard 7/8" line
section....cheap.
They also make the usual 10 kw 5 kw.. 2.5 kw qrp slugs.

It's Not on their website.. nor catalog... but has been around for
years. I'll dig up the model number and post it in a few days.

Fits the Bird 7/8" line sections too !

The 7/8" line sections all have a huge 3/8" inner conductor
tube running down the middle..... where they then neck it down
to the small diam... to take the QC [quick connector's].

They also make 7-16 DIN QC connector's [male or female] for
both the 7/8" + 1 5/8" line sections. You can also get
7/8" EIA flange connector's as QC connector's. Any QC
connector will fit either a 7/8" line section OR a 1 5/8" line
section. The 1 5/8" line section requires an adaptor plate...
in order to accept the QC connectors.

My buddy in Ohio tells me you can also get 50 kw 2-30 mhz
slugs... but didn't say what size line section it was designed
for.

later...... Jim VE7RF
Re: "New" method of fabricating a better chimney

pentalab
 

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

Hi Jim,

I use heatresistant glass cylinders I get made locally and also
use
round teflon covers as you, thats works very well.
All my blowers are made by EBM.
I do not like to boost a tubes rating, I rather prefer then to use
a
bigger one.
I prefer that my GG amps cannot run in too high dissipation at
full
drive. They should have no problem when the antenna gets lost...
### Partially agreed. ..BUT the 3CX-6000A7 is rated at 3.5 A
of plate current CCS. [7 kv under load] .

## as is.... with 2.5 A of plate current @ aprx 6900 V under
load.... DC input is 17.25 kw....... output is 11.5 kw. Anode
diss is 5.75 kw. At 6kw of anode diss.... lower anode
seal [ where the anode meets the ceramic] will be 225 Deg
C !

### I don't like running tubes anywhere near their max
anode diss. The saving grace here is ssb/cw............ the
duty cycle is WAY down. Plus Eimac's air flow specs are
based on a 50 deg C [121 deg F] intake temp... which it's not.

### The point here is.... one would HAVE to increase the anode
diss with more airflow.... in order to operate with 3 - 3.5 A
of plate current.

### Eimac also makes an industrial heater tube.... 3CX-10,000D
with a real small anode... 6.4" diam. I phoned em up.....
they just blew more air through it to get the 10 kw anode diss !


### also note the Eimac 3CX-10,000A7 and also the 3CX-15,000A7
have IDENTICAL physical dimensions in every regard.
What's the diff ??? They just blow more air through the 15K...
that's it.

### Both the 3CX-2500 and the 3CX-3000A7 have IDENTICAL
dimensions/weights. BOTH are rated at 4000 watts of anode
diss... CCS ! Eimac tells me the 2500 was origionally
2.5 kw anode diss.... then they upped the airflow....... ditto
with the 3000A7.



### The 6000A7 is one of the easiset to cool [ and to increase
the anode diss if needed/wanted] . Reason is.... the ceramic
stem is real small diam compared to a YC-156.. 10K, 5K. With
it's 6.125" OD cooler..... you end up with a HUGE fin area
underneath.

## To really utilize this huge fin area underneath... it's gotta
be able to breath right........... and that means the AREA of
the holes /slots in the chassis should be at least the same or
bigger, than the underneath fin AREA. And that means NO
straight up/down chimneys can be used......... hence the 9"
square box we used.

### The Eimac 10,000 chimney is a virtual straight up and down
affair.... and chokes off the airflow from the chassis.

### When I see a 5 HP... 3 phase 208V blower motor for a
pair of 3CX-15,000A7'S...... it makes me gag.

### Compare the pressure requirements of a YC-156 [or a 4CX-
5000] vs a 3CX-6000A7... you will get the idea. [compare em at
the SAME 50 deg C inlet air temp]

Jim VE7RF



73
Peter


--- In ham_amplifiers@..., "pentalab" <jim.thomson@>
wrote:

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].
Re: Can Grid Dissipation in metal GG triodes be increased ????

 

On Sep 22, 2006, at 1:54 PM, pentalab wrote:

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

Jim,

Grid dissipation is measured by ohms law, grid voltage by grid
current.
Since the grid is at ground, you just measure the cathode voltage
with
a scope.
### whoa. Are you saying RF cathode V x DC grid current
= grid diss ????
That's pretty much what Care and Feeding ... ... says. Avg. DC grid-
current is measured with an ordinary panel meter.

### That equates to way below 200 w of grid diss.... based
on 45 ohm input Z... and 800w of drive . I can see we
are well within the grid diss ratings.




For calculation of efficiency you have to deduct the drive power
first
in GG, about 70% of the drive power is seen as output power.
Drive power is not lost totally as with GK.
### I never deduct the drive power... since it really enhances
the eff in the end anyway... another benefit of GG. Bottom line
is... "apparent eff" goes up... anode diss goes down a bit.




If both capacitors of your input network are the same value you
have
no transformation, you will have 50 ohm input from the transceiver
and 50 ohm output to the cathode side.
### yes... u can see that effect on GM3SEK's excellent pi/ pi-l
spreadsheets. Funny how every arrl handbook/qst article
using fixed silver mica's always used same values for C1 +
C2.... which never worked.



I would expect the cathode impedance smaller at that power,
probably
30-40 Ohms.
#### it's about 40-45 ohms. The gain is about 11.54 db at
11.5 kw out.

### Funny thing is... with just 100w of drive... power out is 3
kw [ 3CX-6000A7] It appears on all these big tubes... that
gain is higher with low drive levels... then decreases... with
increasing drive levels.

### The 3000A7 is abt 1500w out with just 50 w of drive.

### Tubes like the higher gain YC-156 have aprx 25 ohm input Z.
Gain is almost quasi proportional between plate load Z and input
Z.




I use that tunable pi-network on my 3CX3K amp, but used a smaller
capacitor on the ouput then on the input. My coil is switched as
well.
I would like to use ganged capacitors there and ganged with a
roller
at the same time, should work with that low circuit Q.
### Henry tried that in the 4 K ultra. Trying to get it to
track was [still is] a real bitch. I wouldn't do it. For
160-10m... u need 4000 pf caps. If u pad smaller 2100 pf caps
like I did for 160m... ur tracking will be out to lunch. You
also seem to get anomoly's from one band to the next.



Any idea of the price of the 4?H roller by multronics?
### No clue It appears identical to their 28 uh unit that
was featured in many qst/ handbook articles over the years...
excpet the little 4.4 uh unit is shorter... and uses 8 ga wire
[.128" solid tinned alloy wire]. I believe the 4.4 uh unit also
has the same tapered pitch at the high freq end.

### Multronics is now a division of Cardwell condenser corp.... I
think it's just cardwell condensercorp.com

Later... Jim VE7RF




73
Peter






Yahoo! Groups Links









R L MEASURES, AG6K. 805-386-3734
r@...
Re: Can Grid Dissipation in metal GG triodes be increased ????

pentalab
 

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

Jim,

Grid dissipation is measured by ohms law, grid voltage by grid
current.
Since the grid is at ground, you just measure the cathode voltage
with
a scope.
### whoa. Are you saying RF cathode V x DC grid current
= grid diss ????

### That equates to way below 200 w of grid diss.... based
on 45 ohm input Z... and 800w of drive . I can see we
are well within the grid diss ratings.




For calculation of efficiency you have to deduct the drive power
first
in GG, about 70% of the drive power is seen as output power.
Drive power is not lost totally as with GK.
### I never deduct the drive power... since it really enhances
the eff in the end anyway... another benefit of GG. Bottom line
is... "apparent eff" goes up... anode diss goes down a bit.




If both capacitors of your input network are the same value you
have
no transformation, you will have 50 ohm input from the transceiver
and 50 ohm output to the cathode side.
### yes... u can see that effect on GM3SEK's excellent pi/ pi-l
spreadsheets. Funny how every arrl handbook/qst article
using fixed silver mica's always used same values for C1 +
C2.... which never worked.



I would expect the cathode impedance smaller at that power,
probably
30-40 Ohms.
#### it's about 40-45 ohms. The gain is about 11.54 db at
11.5 kw out.

### Funny thing is... with just 100w of drive... power out is 3
kw [ 3CX-6000A7] It appears on all these big tubes... that
gain is higher with low drive levels... then decreases... with
increasing drive levels.

### The 3000A7 is abt 1500w out with just 50 w of drive.

### Tubes like the higher gain YC-156 have aprx 25 ohm input Z.
Gain is almost quasi proportional between plate load Z and input
Z.




I use that tunable pi-network on my 3CX3K amp, but used a smaller
capacitor on the ouput then on the input. My coil is switched as
well.
I would like to use ganged capacitors there and ganged with a
roller
at the same time, should work with that low circuit Q.
### Henry tried that in the 4 K ultra. Trying to get it to
track was [still is] a real bitch. I wouldn't do it. For
160-10m... u need 4000 pf caps. If u pad smaller 2100 pf caps
like I did for 160m... ur tracking will be out to lunch. You
also seem to get anomoly's from one band to the next.



Any idea of the price of the 4?H roller by multronics?
### No clue It appears identical to their 28 uh unit that
was featured in many qst/ handbook articles over the years...
excpet the little 4.4 uh unit is shorter... and uses 8 ga wire
[.128" solid tinned alloy wire]. I believe the 4.4 uh unit also
has the same tapered pitch at the high freq end.

### Multronics is now a division of Cardwell condenser corp.... I
think it's just cardwell condensercorp.com

Later... Jim VE7RF




73
Peter
Re: YC-156 amp

pentalab
 

--- In ham_amplifiers@..., Jan Erik Holm <sm2ekm@...>
wrote:

Jim,

Grid drive I suppose? In GG I would guess with 200W drive
maybe 5-6 kW, or?
### 9-12 kw out with 200w of drive. ..easy. [7900 v no load]


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.
#### The trbl with 4-1000's is trying to find good one's
these days. I had single 4-1000's and pairs of em... between
1976- late 80's.

### The YC-156 in GG has a huge amount of gain. 100 w and low
plate v... like 4 kv will do 4 kw out. My buddy had a 4-
1000 amp... he converted to a pair of 8877's.... then later on...
replaced the 2 x 8877's with a single YC-156.... best thing he
ever did.

### They all used a removeable aluminum plate for the tube...
so the plate could be removed... and replaced with another
plate / diff tube/socket combo. Of course all the LC
ratio's on the pi-net had to be changed.

### I'm told the YC-156 has an input Z of 25 ohms.... so base
any tuned inputs around that... and use paralled RG-58 u coax to
make the 25 ohm cable from output of tuned input... to socket.

### also beware.... the YC-156 has 36 pf of anode to grid
C........ which will INCREASE to 50 pf.... when the YC-156 is
bolted to the chassis !!!

### The 3000A7 does the same thing.... anode to grid C is 24
pf.... and rises to 33 pf when plugged into the grid ring.

### The 6000A7 is 24.5 pf anode to grid.... and rises to 36 pf
when plugged in.

### To get these big tubes to work on 20-10m.... you gotta
add .6 uh between plate block cap and tube.... OR just tap
into the 1st .6 uh of main tank coil.... with the vac tune
cap.... amounts to the same thing.

### This will DROP ther plate load Z WAY down.... so the PI
net is designed around this lower value.

### I use GM3SEK's excellent pi pi-L spreadsheet. It factor's
in this L between tube anode and the pi net. Any stray L
between the anode and the input of the PI net will make a HUGE
difference in transformed plate load Z on the higher bands. [I
also use his spread sheet for the pi tuned input calcs]

### also if u have any kind of Z bump bewteen vac load cap and
the vac T/R relay...... you will have a mini PI-L on the high
bands.. esp 10m..... which will put the vac load cap at a sky
high Voltage. 11m ops have used just wire, strap between vac
load cap.. and the vac T/R relay.... and smoked 5 kv rated vac
load caps !!


### I deep sixed 10/12 m from the last bunch of linears I have
built. Also, if you do, beware of trying to re-use the 10m
tank coil tap... on 12M. The Q will sky rocket... and the
circulating currents will cook everything.

Later.... Jim VE7RF


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
Re: YC-156 amp

FRANCIS CARCIA
 

That was my reason for moving to 4CX3000A and bought 6 for $100.

Jan Erik Holm wrote:

Well they are difficult to get stable. They run just
fine now but Ive used 4-1000s for 35 years and
frankly Im a bit bored with them.

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

GGLL wrote:
> 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
>> ----------------
Re: YC-156 amp

 

Yes understand. Well 4-1000As can be made to run very
good, however I just want to try something else.
However those tubes they glow very nice in the dark,
both filament and plates.

73 SM2EKM
-----------

FRANCIS CARCIA wrote:

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
>
Re: YC-156 amp

 

Thanks Tony,

OK 19 dB or so, sounds nice. Yes its a nice tube,
time to retire the old 4-1000A bottles.

As I said it will be a simple swap. I already have
two 7.5 V fil transformers in the box, just have
to run them in series, input Z is close to what
2x4-1000A has and it just needs a tweak, I already
feed the 4-1000s with a big 3-phase power supply,
means I can run the YC-156 at a nice level.

73 Jim SM2EKM
----------------
Tony King - W4ZT wrote:

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
Re: YC-156 amp

 

Well they are difficult to get stable. They run just
fine now but Ive used 4-1000s for 35 years and
frankly Im a bit bored with them.

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

GGLL wrote:

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
----------------
Re: YC-156 amp

Tony King - W4ZT
 

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?

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
Re: YC-156 amp

FRANCIS CARCIA
 

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)" 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
>

Re: YC-156 amp

GGLL
 

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
----------------
Re: Need schematic or transistor data (for Henry SS amp)

GGLL
 

No, they're not for feedback; these resistors are from base to ground and even from base to base, there are three, and are different types than those used in the attenuator for example, look modern; besides, the input attenuator looks good (I did not measure individual resistor values yet, they're all old 2 watt dark brown, carbon types). Anyway, today I'll get a better idea of how they're connected.
If I could have some data about that CD4778.....
Thanks

Best regards
Guillermo - LU8EYW.

craxd escribi:

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
Re: Censorship/Administrator

 

On Sep 21, 2006, at 6:06 PM, bill_w4zv wrote:

--- In ham_amplifiers@..., R L Measures <r@...> wrote:

I got booted off of Topband for questioning questionable technical
statements bu Tom RAUCH, W8JI. Bill, are you a friend of Tom?
Wrong again Rich. I'm the moderator for Topband
Were you always the Moderator of Topband?

and I didn't boot you
off...so please fabricate another story about why you voluntarily left.

I thought maybe it was because you realized you didn't know what you
were talking about regarding 160 meters. I got a chuckle out of your
comment below about the conductivity of freshwater versus saltwater.
:-)
The RF conductivity or the DC conductivity?

73, Bill

msg00111.html

AG6K wrote:
Howard -- Water has a dielectric constant of c. 79 whether it is
salted or pure, so for RF purposes, a freshwater marsh conducts as
well as a saltwater marsh.

Rich, you are mixing dielectric constant with conductivity.
Conductivity is the key parameter and there is a huge difference
between salt water and fresh water:

Surface Type Dielectric Constant Conductivity (S/m)
Fresh Water 80 0.001
Salt Water 81 5.0

73, Bill W4ZV

P.S.

Figure R3 of 47 CFR 73.190 of the Commission's Rules contains a map of
the estimated effective ground conductivity in the United States. This
data is used to predict the propagation of AM signals across the
United States. A higher ground conductivity indicates better AM
propagation characteristics. The maps below show that the ground
conductivity in the U.S. ranges between 0.5 and 30 millimhos per
meter. The conductivity of seawater is 5,000 millimhos per meter,
resulting in the best propagation of AM signals.

(5,000 millimhos per meter is identical to 5.0 Siemens per meter...de
W4ZV).








Yahoo! Groups Links









R L MEASURES, AG6K. 805-386-3734
r@...
Re: Censorship/Administrator

 

On Sep 22, 2006, at 1:00 AM, Jan Erik Holm wrote:

This is all I know on the matter Rich, however I suppose
it could have happned in a car.
Thanks, Jim. RIP, Bill Fisher.

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

R L Measures wrote:
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.



Yahoo! Groups Links










R L MEASURES, AG6K. 805-386-3734
r@...
Re: YC-156 amp

Mike&#92;(W5UC&#92;) & Kathy&#92;(K5MWH&#92;)
 

¿ªÔÆÌåÓý

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 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
>

Re: Drake L7

 

I agree with Will. Why rebuild, I would just fix whats
broken and continue to use it.

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

tm303 wrote:

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
YC-156 amp

 

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
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