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Re: Reply from ECONCO

 

Will Econco? rebuild a 3cx3000F1 into a 3cx3000F7. I have a few genuine F1's which I wish were F7's

Anyone know if this is possible?

Henry


Plate blocking caps YC156

 

Anyone suggest a plate blocking cap brand?

The only capacitors that i can? get RF current data on is the HT57's. I was thinking of using a couple of? HT57 1000pf in parallel. Its really hard getting getting RF current data. Anything without RF current data I pressume is just ordinary? non RF rated capacitors. RFPARTS publishes very little RF current data so you dont know what you buying. What are people using on YC156 type amps for 160 through to 10. The Pancake Dralorics are massive? and the current seems limited on the higher frequencies that is for the big 6 or 8 inch pancake types.

Henry


Re: 3CX3000F7 10-80m

 

A? 50 ohm? glitch? resistor...and a fast,? correctly? sized / rated HV? fuse? will? save? just? about? any fault.?
Note the? part? about correctly? sized? HV? fuse.? 1A? for? a 8877,? not? 3A.
For? 3CX-3000A7? and? bigger? tubes, 50? ohms? is as low as? you? want for? the? glitch? resistor.?
HV fuse? 1st.? Glitch resistor on? outboard side? of? fuse.?

50? ohm? glitch R......? ?LIMITS? fault? current? to a safe? value.
? HV fuse INTERRUPTS? ?fault? current.....? and? typ? <2msecs.? ?

Don't? do? silly? stuff,? like a 10-15 ohm? glitch R...and? NO? ?HV? fuse......? you? will? do? severe? damage.

Jim? ?VE7RF


Re: Coil 3.72 software

 



Above? is? the? zip? file.? ? Note, SS? ?has? been? removed? from? the? master? list.
Shoulda left it on.? SS? is? so? bad,? it was? at the? bottom? of? the? previous? list.?

Jim? ?VE7RF?


Re: Coil 3.72 software

 

Latest? version? is? available...called coil 3.77? ?

3.77? has? replaced 3.72

Jim? VE7RF


Re: 3CX3000F7 10-80m

 

Elevate the? choke? above the? chassis,? and u? can? increase? the? B+? through? the? roof.? The? 4.5 kv rating is? cuz the bottom? transverse screw? is? extremely? close to chassis.?

2 x HT-57 bypass? caps a few? inches apart? on? chassis.? Flat? AL strap,? like? 1" x 3" x 1/8"? thick? ,? between? tops? of? caps.? Choke dead center, on? top? side? of al? bar.

Bottom? lug? of? choke? bonded to? bar.? B+? fed? to? bar.? ?Problem? solved,? run? all the B+? u? want.? 8 kv,? no? problem.? ? u? can? also? use? 2 x? identical? assy's in parallel,? spaced well? apart.....and? run? 3A? CCS? ?

It? appears? the? ameritron? choke in? the? pix? is? way? too? close? to the? rear? wall.? that? can? really? screw? things? up...and? fast.? ?

Jim? ?VE7RF


Re: 3CX3000F7 10-80m

 

?
Im still laughing Dave.
?
Some get a litle anal when it comes to hams pushing things a bit but we are not in the commercial or military world. Blowing a choke with that tube only hurts the choke.
?
BTW the big B$W choke mentioned earlier was ferrite loaded and hams blew them left and right without pushing the ratings.
?
I still have a bad one returned from a customer and quit selling them ages ago.
?
Carl
?
Carl

----- Original Message -----
Sent: Tuesday, December 03, 2019 4:35 AM
Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

Some joke, Peter. ?One failure in nearly 20 years.?

The HRC fuse has blown twice during that time - once when the top band antenna broke and once when a gamma matched beam flashed over.

It¡¯s not perfect, I¡¯ll concede that.?

73
Dave?




On Monday, December 2, 2019, 8:08 pm, Peter Voelpel <dj7ww@...> wrote:

It?s an expensive fuse, not more.

To install it as an rf choke into a 3CX3K amp must be a joke.

?

73

Peter, DJ7WW

?


From: [email protected] [mailto:[email protected]] On Behalf Of Jeff AC0C
Sent: Montag, 2. Dezember 2019 18:43
To: [email protected]
Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

?

The choke is a lot more robust than you would think.? I've had a couple of them pop over the years but tracked that down to a resonance (AKA idiot builder error) each time.? Fix the resonance (reposition), patch the choke and back in biz.? The size of the choke wire from a "can it carry the plate current" standpoint is definitely fine for typical use - unless you are in the fire breathing realm.?

If you don't believe it and want to feel better about it, hang a few sizes of mid 30's gauge wire on a constant current supply and see how just high you have to bump that current to get it to open up.? You may be surprised.

73/jeff/ac0c

alpha-charlie-zero-charlie
 ?
 ?

On 12/2/19 10:13 AM, cturnertuning wrote:

This confirms your choke is the "fuse" in your amplifier. If you are ok with that Dave, then great. I have one in an AM plate modulated amplifier with a pair of 4-400s modulated by a pair of 304TLs. The choke has survived. I have had failures but was running them past the ratings. Did your choke unravel?? That seems to be the type of failure with these. One good bang and they un wind on the form.

C

On 11/30/2019 7:15 PM, DAVE WHITE via Groups.Io wrote:

¡°Ratings are guidelines¡± - yeah that what this guy at Essen Motor Show said this weekend (picture attached)?

Inline            image

?

?

In my 3CX3000A7 amp I used a very similar choke (in fact it looks the same) bought from RF Parts. ?I think it too is rated at 4kv 1.5A. ?

?

?

I¡¯ve had one failure in 18 years with the amp and that was the choke. ?I use a glitch resistor and an HRC fuse inthe ?HT line which worked fine and protected the amp when the insulator at the end of my top band 3/8 inverted L exploded one night, thus leaving the choke ok. ?But one day about 10 years ago the choke just went BANG. ?I never worked out why. ?I replaced it with another identical one and (touch wood) it¡¯s been ok since.?

?

I know that B&W used to make a much higher rated choke years ago but they seem to be unobtainium now. ?I run 5.5kv resting voltage on the anode so always knew that the plate choke was the weakest point.?

?

That looks like a nice amp in the pictures.

?

I used two rollercoasters and two vacuum capacitors as a Pi-L 10-160m, by the way. ?

?

I bought a mix of A7 and F7 tubes from the Dayton flea market so bought an A7 socket and removed the filament rings and flying leads from the F7s with a little heat. ?They¡¯re just held on there with soft solder. ?The idea was that a tube change is much easier.?

73 Dave?


On Sunday, December 1, 2019, 2:30 am, Carl <km1h@...> wrote:

Yep, while the designer ran a full bore 2 hole AL-1500 with no problems the company went to a lower rating to minimize warranty issues.

?

Note I also stressed the layout as many Hammy Hambone amp builders havent a clue about coupling and "parasitic" resonances..Not AG6K parasitics!?

?

Carl

----- Original Message -----

Sent: Friday, November 29, 2019 12:27 AM

Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

?

Ratings are guidelines.

73, Alek
VK6APK

On 29/11/2019 10:14 AM, cturnertuning wrote:

Not really. Its rated at 4kv max and 1.5 amp peak. It is the weak link for sure. But if it works it works. Better have a glitch. One arc and its done. In this example its a fuse.:)

?

Sent from my T-Mobile 4G LTE device

?

------ Original message------

From: Carl

Date: Thu, Nov 28, 2019 6:25 PM

Cc:

Subject:Re: [ham-amplifiers] 3CX3000F7 10-80m

?

The Ameritron choke will easily handle 2A?from that tube on CW and SSB.

It is also well placed for minimum coupling.

?

Carl

----- Original Message -----

Sent: Wednesday, November 27, 2019 10:40 AM

Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

?

That little Ameritron plate choke is screaming for its life :) Very cool amplifier!

?

On 11/26/2019 6:53 PM, Mike via wrote:

My latest amplifier.

-- 
Please let me quote you for your parts needs!
I offer a discount on Protunes with parts order!
Clark Turner
480-695-2898
??? 

?

-- 
>From sunny Binningup
 ?
 ?
 ?
Family Businesses:
SP Electrical. 
The Velvet Fox. 
Smart Design Electrical. 
Perth Interiors. 
-- 
Please let me quote you for your parts needs!
I offer a discount on Protunes with parts order!
Clark Turner
480-695-2898


Re: 3CX3000F7 10-80m

 

Some joke, Peter. ?One failure in nearly 20 years.?

The HRC fuse has blown twice during that time - once when the top band antenna broke and once when a gamma matched beam flashed over.

It¡¯s not perfect, I¡¯ll concede that.?

73
Dave?




On Monday, December 2, 2019, 8:08 pm, Peter Voelpel <dj7ww@...> wrote:

It?s an expensive fuse, not more.

To install it as an rf choke into a 3CX3K amp must be a joke.

?

73

Peter, DJ7WW

?


From: [email protected] [mailto:[email protected]] On Behalf Of Jeff AC0C
Sent: Montag, 2. Dezember 2019 18:43
To: [email protected]
Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

?

The choke is a lot more robust than you would think.? I've had a couple of them pop over the years but tracked that down to a resonance (AKA idiot builder error) each time.? Fix the resonance (reposition), patch the choke and back in biz.? The size of the choke wire from a "can it carry the plate current" standpoint is definitely fine for typical use - unless you are in the fire breathing realm.?

If you don't believe it and want to feel better about it, hang a few sizes of mid 30's gauge wire on a constant current supply and see how just high you have to bump that current to get it to open up.? You may be surprised.

73/jeff/ac0c

alpha-charlie-zero-charlie
 ?
 ?

On 12/2/19 10:13 AM, cturnertuning wrote:

This confirms your choke is the "fuse" in your amplifier. If you are ok with that Dave, then great. I have one in an AM plate modulated amplifier with a pair of 4-400s modulated by a pair of 304TLs. The choke has survived. I have had failures but was running them past the ratings. Did your choke unravel?? That seems to be the type of failure with these. One good bang and they un wind on the form.

C

On 11/30/2019 7:15 PM, DAVE WHITE via Groups.Io wrote:

¡°Ratings are guidelines¡± - yeah that what this guy at Essen Motor Show said this weekend (picture attached)?

Inline            image

?

?

In my 3CX3000A7 amp I used a very similar choke (in fact it looks the same) bought from RF Parts. ?I think it too is rated at 4kv 1.5A. ?

?

?

I¡¯ve had one failure in 18 years with the amp and that was the choke. ?I use a glitch resistor and an HRC fuse inthe ?HT line which worked fine and protected the amp when the insulator at the end of my top band 3/8 inverted L exploded one night, thus leaving the choke ok. ?But one day about 10 years ago the choke just went BANG. ?I never worked out why. ?I replaced it with another identical one and (touch wood) it¡¯s been ok since.?

?

I know that B&W used to make a much higher rated choke years ago but they seem to be unobtainium now. ?I run 5.5kv resting voltage on the anode so always knew that the plate choke was the weakest point.?

?

That looks like a nice amp in the pictures.

?

I used two rollercoasters and two vacuum capacitors as a Pi-L 10-160m, by the way. ?

?

I bought a mix of A7 and F7 tubes from the Dayton flea market so bought an A7 socket and removed the filament rings and flying leads from the F7s with a little heat. ?They¡¯re just held on there with soft solder. ?The idea was that a tube change is much easier.?

73 Dave?


On Sunday, December 1, 2019, 2:30 am, Carl <km1h@...> wrote:

Yep, while the designer ran a full bore 2 hole AL-1500 with no problems the company went to a lower rating to minimize warranty issues.

?

Note I also stressed the layout as many Hammy Hambone amp builders havent a clue about coupling and "parasitic" resonances..Not AG6K parasitics!?

?

Carl

----- Original Message -----

Sent: Friday, November 29, 2019 12:27 AM

Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

?

Ratings are guidelines.

73, Alek
VK6APK

On 29/11/2019 10:14 AM, cturnertuning wrote:

Not really. Its rated at 4kv max and 1.5 amp peak. It is the weak link for sure. But if it works it works. Better have a glitch. One arc and its done. In this example its a fuse.:)

?

Sent from my T-Mobile 4G LTE device

?

------ Original message------

From: Carl

Date: Thu, Nov 28, 2019 6:25 PM

Cc:

Subject:Re: [ham-amplifiers] 3CX3000F7 10-80m

?

The Ameritron choke will easily handle 2A?from that tube on CW and SSB.

It is also well placed for minimum coupling.

?

Carl

----- Original Message -----

Sent: Wednesday, November 27, 2019 10:40 AM

Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

?

That little Ameritron plate choke is screaming for its life :) Very cool amplifier!

?

On 11/26/2019 6:53 PM, Mike via wrote:

My latest amplifier.

-- 
Please let me quote you for your parts needs!
I offer a discount on Protunes with parts order!
Clark Turner
480-695-2898
??? 

?

-- 
>From sunny Binningup
 ?
 ?
 ?
Family Businesses:
SP Electrical. 
The Velvet Fox. 
Smart Design Electrical. 
Perth Interiors. 
-- 
Please let me quote you for your parts needs!
I offer a discount on Protunes with parts order!
Clark Turner
480-695-2898


Re: 3CX3000F7 10-80m

 

¿ªÔÆÌåÓý

It?s an expensive fuse, not more.

To install it as an rf choke into a 3CX3K amp must be a joke.

?

73

Peter, DJ7WW

?


From: [email protected] [mailto:[email protected]] On Behalf Of Jeff AC0C
Sent: Montag, 2. Dezember 2019 18:43
To: [email protected]
Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

?

The choke is a lot more robust than you would think.? I've had a couple of them pop over the years but tracked that down to a resonance (AKA idiot builder error) each time.? Fix the resonance (reposition), patch the choke and back in biz.? The size of the choke wire from a "can it carry the plate current" standpoint is definitely fine for typical use - unless you are in the fire breathing realm.?

If you don't believe it and want to feel better about it, hang a few sizes of mid 30's gauge wire on a constant current supply and see how just high you have to bump that current to get it to open up.? You may be surprised.

73/jeff/ac0c

alpha-charlie-zero-charlie
?
?

On 12/2/19 10:13 AM, cturnertuning wrote:

This confirms your choke is the "fuse" in your amplifier. If you are ok with that Dave, then great. I have one in an AM plate modulated amplifier with a pair of 4-400s modulated by a pair of 304TLs. The choke has survived. I have had failures but was running them past the ratings. Did your choke unravel?? That seems to be the type of failure with these. One good bang and they un wind on the form.

C

On 11/30/2019 7:15 PM, DAVE WHITE via Groups.Io wrote:

¡°Ratings are guidelines¡± - yeah that what this guy at Essen Motor Show said this weekend (picture attached)?

?

?

In my 3CX3000A7 amp I used a very similar choke (in fact it looks the same) bought from RF Parts. ?I think it too is rated at 4kv 1.5A. ?

?

?

I¡¯ve had one failure in 18 years with the amp and that was the choke. ?I use a glitch resistor and an HRC fuse inthe ?HT line which worked fine and protected the amp when the insulator at the end of my top band 3/8 inverted L exploded one night, thus leaving the choke ok. ?But one day about 10 years ago the choke just went BANG. ?I never worked out why. ?I replaced it with another identical one and (touch wood) it¡¯s been ok since.?

?

I know that B&W used to make a much higher rated choke years ago but they seem to be unobtainium now. ?I run 5.5kv resting voltage on the anode so always knew that the plate choke was the weakest point.?

?

That looks like a nice amp in the pictures.

?

I used two rollercoasters and two vacuum capacitors as a Pi-L 10-160m, by the way. ?

?

I bought a mix of A7 and F7 tubes from the Dayton flea market so bought an A7 socket and removed the filament rings and flying leads from the F7s with a little heat. ?They¡¯re just held on there with soft solder. ?The idea was that a tube change is much easier.?

73 Dave?


On Sunday, December 1, 2019, 2:30 am, Carl <km1h@...> wrote:

Yep, while the designer ran a full bore 2 hole AL-1500 with no problems the company went to a lower rating to minimize warranty issues.

?

Note I also stressed the layout as many Hammy Hambone amp builders havent a clue about coupling and "parasitic" resonances..Not AG6K parasitics!?

?

Carl

----- Original Message -----

Sent: Friday, November 29, 2019 12:27 AM

Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

?

Ratings are guidelines.

73, Alek
VK6APK

On 29/11/2019 10:14 AM, cturnertuning wrote:

Not really. Its rated at 4kv max and 1.5 amp peak. It is the weak link for sure. But if it works it works. Better have a glitch. One arc and its done. In this example its a fuse.:)

?

Sent from my T-Mobile 4G LTE device

?

------ Original message------

From: Carl

Date: Thu, Nov 28, 2019 6:25 PM

Cc:

Subject:Re: [ham-amplifiers] 3CX3000F7 10-80m

?

The Ameritron choke will easily handle 2A?from that tube on CW and SSB.

It is also well placed for minimum coupling.

?

Carl

----- Original Message -----

Sent: Wednesday, November 27, 2019 10:40 AM

Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

?

That little Ameritron plate choke is screaming for its life :) Very cool amplifier!

?

On 11/26/2019 6:53 PM, Mike via wrote:

My latest amplifier.

-- 
Please let me quote you for your parts needs!
I offer a discount on Protunes with parts order!
Clark Turner
480-695-2898
??? 

?

-- 
>From sunny Binningup
?
?
?
Family Businesses:
SP Electrical. 
The Velvet Fox. 
Smart Design Electrical. 
Perth Interiors. 
-- 
Please let me quote you for your parts needs!
I offer a discount on Protunes with parts order!
Clark Turner
480-695-2898


Re: 3CX3000F7 10-80m

 

¿ªÔÆÌåÓý

The choke is a lot more robust than you would think.? I've had a couple of them pop over the years but tracked that down to a resonance (AKA idiot builder error) each time.? Fix the resonance (reposition), patch the choke and back in biz.? The size of the choke wire from a "can it carry the plate current" standpoint is definitely fine for typical use - unless you are in the fire breathing realm.?

If you don't believe it and want to feel better about it, hang a few sizes of mid 30's gauge wire on a constant current supply and see how just high you have to bump that current to get it to open up.? You may be surprised.

73/jeff/ac0c
alpha-charlie-zero-charlie



On 12/2/19 10:13 AM, cturnertuning wrote:

This confirms your choke is the "fuse" in your amplifier. If you are ok with that Dave, then great. I have one in an AM plate modulated amplifier with a pair of 4-400s modulated by a pair of 304TLs. The choke has survived. I have had failures but was running them past the ratings. Did your choke unravel?? That seems to be the type of failure with these. One good bang and they un wind on the form.

C

On 11/30/2019 7:15 PM, DAVE WHITE via Groups.Io wrote:
¡°Ratings are guidelines¡± - yeah that what this guy at Essen Motor Show said this weekend (picture attached)?


In my 3CX3000A7 amp I used a very similar choke (in fact it looks the same) bought from RF Parts. ?I think it too is rated at 4kv 1.5A. ?


I¡¯ve had one failure in 18 years with the amp and that was the choke. ?I use a glitch resistor and an HRC fuse inthe ?HT line which worked fine and protected the amp when the insulator at the end of my top band 3/8 inverted L exploded one night, thus leaving the choke ok. ?But one day about 10 years ago the choke just went BANG. ?I never worked out why. ?I replaced it with another identical one and (touch wood) it¡¯s been ok since.?

I know that B&W used to make a much higher rated choke years ago but they seem to be unobtainium now. ?I run 5.5kv resting voltage on the anode so always knew that the plate choke was the weakest point.?

That looks like a nice amp in the pictures.

I used two rollercoasters and two vacuum capacitors as a Pi-L 10-160m, by the way. ?

I bought a mix of A7 and F7 tubes from the Dayton flea market so bought an A7 socket and removed the filament rings and flying leads from the F7s with a little heat. ?They¡¯re just held on there with soft solder. ?The idea was that a tube change is much easier.?

73 Dave?



On Sunday, December 1, 2019, 2:30 am, Carl <km1h@...> wrote:

Yep, while the designer ran a full bore 2 hole AL-1500 with no problems the company went to a lower rating to minimize warranty issues.
?
Note I also stressed the layout as many Hammy Hambone amp builders havent a clue about coupling and "parasitic" resonances..Not AG6K parasitics!?
?
Carl
----- Original Message -----
Sent: Friday, November 29, 2019 12:27 AM
Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

Ratings are guidelines.

73, Alek
VK6APK

On 29/11/2019 10:14 AM, cturnertuning wrote:
Not really. Its rated at 4kv max and 1.5 amp peak. It is the weak link for sure. But if it works it works. Better have a glitch. One arc and its done. In this example its a fuse.:)

Sent from my T-Mobile 4G LTE device

------ Original message------
From: Carl
Date: Thu, Nov 28, 2019 6:25 PM
Cc:
Subject:Re: [ham-amplifiers] 3CX3000F7 10-80m

The Ameritron choke will easily handle 2A?from that tube on CW and SSB.
It is also well placed for minimum coupling.
?
Carl
----- Original Message -----
Sent: Wednesday, November 27, 2019 10:40 AM
Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

That little Ameritron plate choke is screaming for its life :) Very cool amplifier!


On 11/26/2019 6:53 PM, Mike via wrote:
My latest amplifier.
-- 
Please let me quote you for your parts needs!
I offer a discount on Protunes with parts order!
Clark Turner
480-695-2898
    

-- 
>From sunny Binningup



Family Businesses:
SP Electrical. 
The Velvet Fox. 
Smart Design Electrical. 
Perth Interiors. 
-- 
Please let me quote you for your parts needs!
I offer a discount on Protunes with parts order!
Clark Turner
480-695-2898


Re: 3CX3000F7 10-80m

 

¿ªÔÆÌåÓý

This confirms your choke is the "fuse" in your amplifier. If you are ok with that Dave, then great. I have one in an AM plate modulated amplifier with a pair of 4-400s modulated by a pair of 304TLs. The choke has survived. I have had failures but was running them past the ratings. Did your choke unravel?? That seems to be the type of failure with these. One good bang and they un wind on the form.

C

On 11/30/2019 7:15 PM, DAVE WHITE via Groups.Io wrote:
¡°Ratings are guidelines¡± - yeah that what this guy at Essen Motor Show said this weekend (picture attached)?


In my 3CX3000A7 amp I used a very similar choke (in fact it looks the same) bought from RF Parts. ?I think it too is rated at 4kv 1.5A. ?


I¡¯ve had one failure in 18 years with the amp and that was the choke. ?I use a glitch resistor and an HRC fuse inthe ?HT line which worked fine and protected the amp when the insulator at the end of my top band 3/8 inverted L exploded one night, thus leaving the choke ok. ?But one day about 10 years ago the choke just went BANG. ?I never worked out why. ?I replaced it with another identical one and (touch wood) it¡¯s been ok since.?

I know that B&W used to make a much higher rated choke years ago but they seem to be unobtainium now. ?I run 5.5kv resting voltage on the anode so always knew that the plate choke was the weakest point.?

That looks like a nice amp in the pictures.

I used two rollercoasters and two vacuum capacitors as a Pi-L 10-160m, by the way. ?

I bought a mix of A7 and F7 tubes from the Dayton flea market so bought an A7 socket and removed the filament rings and flying leads from the F7s with a little heat. ?They¡¯re just held on there with soft solder. ?The idea was that a tube change is much easier.?

73 Dave?



On Sunday, December 1, 2019, 2:30 am, Carl <km1h@...> wrote:

Yep, while the designer ran a full bore 2 hole AL-1500 with no problems the company went to a lower rating to minimize warranty issues.
?
Note I also stressed the layout as many Hammy Hambone amp builders havent a clue about coupling and "parasitic" resonances..Not AG6K parasitics!?
?
Carl
----- Original Message -----
Sent: Friday, November 29, 2019 12:27 AM
Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

Ratings are guidelines.

73, Alek
VK6APK

On 29/11/2019 10:14 AM, cturnertuning wrote:
Not really. Its rated at 4kv max and 1.5 amp peak. It is the weak link for sure. But if it works it works. Better have a glitch. One arc and its done. In this example its a fuse.:)

Sent from my T-Mobile 4G LTE device

------ Original message------
From: Carl
Date: Thu, Nov 28, 2019 6:25 PM
Cc:
Subject:Re: [ham-amplifiers] 3CX3000F7 10-80m

The Ameritron choke will easily handle 2A?from that tube on CW and SSB.
It is also well placed for minimum coupling.
?
Carl
----- Original Message -----
Sent: Wednesday, November 27, 2019 10:40 AM
Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

That little Ameritron plate choke is screaming for its life :) Very cool amplifier!


On 11/26/2019 6:53 PM, Mike via wrote:
My latest amplifier.
-- 
Please let me quote you for your parts needs!
I offer a discount on Protunes with parts order!
Clark Turner
480-695-2898
    

-- 
>From sunny Binningup



Family Businesses:
SP Electrical. 
The Velvet Fox. 
Smart Design Electrical. 
Perth Interiors. 
-- 
Please let me quote you for your parts needs!
I offer a discount on Protunes with parts order!
Clark Turner
480-695-2898


Re: 3CX3000F7 10-80m

 

¡°Ratings are guidelines¡± - yeah that what this guy at Essen Motor Show said this weekend (picture attached)?
Inline image


In my 3CX3000A7 amp I used a very similar choke (in fact it looks the same) bought from RF Parts. ?I think it too is rated at 4kv 1.5A. ?


I¡¯ve had one failure in 18 years with the amp and that was the choke. ?I use a glitch resistor and an HRC fuse inthe ?HT line which worked fine and protected the amp when the insulator at the end of my top band 3/8 inverted L exploded one night, thus leaving the choke ok. ?But one day about 10 years ago the choke just went BANG. ?I never worked out why. ?I replaced it with another identical one and (touch wood) it¡¯s been ok since.?

I know that B&W used to make a much higher rated choke years ago but they seem to be unobtainium now. ?I run 5.5kv resting voltage on the anode so always knew that the plate choke was the weakest point.?

That looks like a nice amp in the pictures.

I used two rollercoasters and two vacuum capacitors as a Pi-L 10-160m, by the way. ?

I bought a mix of A7 and F7 tubes from the Dayton flea market so bought an A7 socket and removed the filament rings and flying leads from the F7s with a little heat. ?They¡¯re just held on there with soft solder. ?The idea was that a tube change is much easier.?

73 Dave?



On Sunday, December 1, 2019, 2:30 am, Carl <km1h@...> wrote:

Yep, while the designer ran a full bore 2 hole AL-1500 with no problems the company went to a lower rating to minimize warranty issues.
?
Note I also stressed the layout as many Hammy Hambone amp builders havent a clue about coupling and "parasitic" resonances..Not AG6K parasitics!?
?
Carl
----- Original Message -----
Sent: Friday, November 29, 2019 12:27 AM
Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

Ratings are guidelines.

73, Alek
VK6APK

On 29/11/2019 10:14 AM, cturnertuning wrote:
Not really. Its rated at 4kv max and 1.5 amp peak. It is the weak link for sure. But if it works it works. Better have a glitch. One arc and its done. In this example its a fuse.:)

Sent from my T-Mobile 4G LTE device

------ Original message------
From: Carl
Date: Thu, Nov 28, 2019 6:25 PM
Cc:
Subject:Re: [ham-amplifiers] 3CX3000F7 10-80m

The Ameritron choke will easily handle 2A?from that tube on CW and SSB.
It is also well placed for minimum coupling.
?
Carl
----- Original Message -----
Sent: Wednesday, November 27, 2019 10:40 AM
Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

That little Ameritron plate choke is screaming for its life :) Very cool amplifier!


On 11/26/2019 6:53 PM, Mike via wrote:
My latest amplifier.
-- 
Please let me quote you for your parts needs!
I offer a discount on Protunes with parts order!
Clark Turner
480-695-2898
    

-- 
From sunny Binningup



Family Businesses:
SP Electrical. 
The Velvet Fox. 
Smart Design Electrical. 
Perth Interiors. 


Re: 3CX3000F7 10-80m

 

?
Yep, while the designer ran a full bore 2 hole AL-1500 with no problems the company went to a lower rating to minimize warranty issues.
?
Note I also stressed the layout as many Hammy Hambone amp builders havent a clue about coupling and "parasitic" resonances..Not AG6K parasitics!?
?
Carl

----- Original Message -----
Sent: Friday, November 29, 2019 12:27 AM
Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

Ratings are guidelines.

73, Alek
VK6APK

On 29/11/2019 10:14 AM, cturnertuning wrote:
Not really. Its rated at 4kv max and 1.5 amp peak. It is the weak link for sure. But if it works it works. Better have a glitch. One arc and its done. In this example its a fuse.:)

Sent from my T-Mobile 4G LTE device

------ Original message------
From: Carl
Date: Thu, Nov 28, 2019 6:25 PM
Cc:
Subject:Re: [ham-amplifiers] 3CX3000F7 10-80m

The Ameritron choke will easily handle 2A?from that tube on CW and SSB.
It is also well placed for minimum coupling.
?
Carl
----- Original Message -----
Sent: Wednesday, November 27, 2019 10:40 AM
Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

That little Ameritron plate choke is screaming for its life :) Very cool amplifier!


On 11/26/2019 6:53 PM, Mike via wrote:
My latest amplifier.
-- 
Please let me quote you for your parts needs!
I offer a discount on Protunes with parts order!
Clark Turner
480-695-2898
    

-- 
From sunny Binningup



Family Businesses:
SP Electrical. 
The Velvet Fox. 
Smart Design Electrical. 
Perth Interiors. 


Re: Hello and a question

jeff austin
 


The only issue that may occur is sourcing the valves for the Alpha. When last checked they were made of unobtanium rgds
Jeff/9y4j?

On Wed, Nov 27, 2019 at 9:24, Jim Strohm
<jim.strohm@...> wrote:
Depends on what "cheaper" means.? Too many hams will cheap out at every possible opportunity, frequently to their detriment later.

You can see today that the Alpha has a much greater retained value.? It probably has better engineering.? Another consideration is the availability of replacement finals down the line.?

As a perennial contributor here used to say, "horses for courses."? Your considerations for amp purchase won't be the same as those of other hams.? If it's ONLY "cheap" -- then I have a D&A Phantom amp I'll sell for real cheap.

73
Jim N6OTQ

On Wed, Nov 27, 2019 at 4:03 AM David Perry <bumbledp@...> wrote:
Hi guys.? Ive just been subscribed to this group.? Greetings one and all.

Q: ?Alpha 76 or FL2100B amp...which to buy.? I have seen one of each at reasonable prices.? I see the 2100 has no top band (pity) and the Alpha looks cosmetically a bit better but the 2100 is cheaper...by far.


Any advice?


73
--
David G4YVM


Re: Hello and a question

jeff austin
 

The only issue with the Alpha 76, that may occur is the scarcity of valves rgds
Jeff/9y4j


On Wed, Nov 27, 2019 at 9:24, Jim Strohm
<jim.strohm@...> wrote:
Depends on what "cheaper" means.? Too many hams will cheap out at every possible opportunity, frequently to their detriment later.

You can see today that the Alpha has a much greater retained value.? It probably has better engineering.? Another consideration is the availability of replacement finals down the line.?

As a perennial contributor here used to say, "horses for courses."? Your considerations for amp purchase won't be the same as those of other hams.? If it's ONLY "cheap" -- then I have a D&A Phantom amp I'll sell for real cheap.

73
Jim N6OTQ

On Wed, Nov 27, 2019 at 4:03 AM David Perry <bumbledp@...> wrote:
Hi guys.? Ive just been subscribed to this group.? Greetings one and all.

Q: ?Alpha 76 or FL2100B amp...which to buy.? I have seen one of each at reasonable prices.? I see the 2100 has no top band (pity) and the Alpha looks cosmetically a bit better but the 2100 is cheaper...by far.


Any advice?


73
--
David G4YVM


Re: 3CX3000F7 10-80m

 

That choke is meant for small desk top amps with small tubes. Any commercial 3000 amp would have a much larger choke or two chokes. I have three of those failed here from different amps and olate modulated amps. If you get a flash over or surpass the current rating it will expand and unwind. I tried to run a pair of 3-1000z tubes at 5000 to 6000 volts and every time they failed. Finally went to a much larger choke. You might get away with it for now but not at high power and not if you you have an event at tube side or tank.?

Sent from my T-Mobile 4G LTE device

------ Original message------
From: Alek Petkovic
Date: Thu, Nov 28, 2019 10:27 PM
Cc: cturnertuning;Carl;
Subject:Re: [ham-amplifiers] 3CX3000F7 10-80m

Ratings are guidelines.

73, Alek
VK6APK

On 29/11/2019 10:14 AM, cturnertuning wrote:
Not really. Its rated at 4kv max and 1.5 amp peak. It is the weak link for sure. But if it works it works. Better have a glitch. One arc and its done. In this example its a fuse.:)

Sent from my T-Mobile 4G LTE device

------ Original message------
From: Carl
Date: Thu, Nov 28, 2019 6:25 PM
Cc:
Subject:Re: [ham-amplifiers] 3CX3000F7 10-80m

The Ameritron choke will easily handle 2A?from that tube on CW and SSB.
It is also well placed for minimum coupling.
?
Carl
----- Original Message -----
To: [email protected]
Sent: Wednesday, November 27, 2019 10:40 AM
Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

That little Ameritron plate choke is screaming for its life :) Very cool amplifier!


On 11/26/2019 6:53 PM, Mike via wrote:
My latest amplifier.
-- 
Please let me quote you for your parts needs!
I offer a discount on Protunes with parts order!
Clark Turner
480-695-2898
    

-- 
From sunny Binningup



Family Businesses:
SP Electrical. 
The Velvet Fox. 
Smart Design Electrical. 
Perth Interiors. 


Re: 3CX3000F7 10-80m

 

¿ªÔÆÌåÓý

Ratings are guidelines.

73, Alek
VK6APK

On 29/11/2019 10:14 AM, cturnertuning wrote:
Not really. Its rated at 4kv max and 1.5 amp peak. It is the weak link for sure. But if it works it works. Better have a glitch. One arc and its done. In this example its a fuse.:)

Sent from my T-Mobile 4G LTE device

------ Original message------
From: Carl
Date: Thu, Nov 28, 2019 6:25 PM
Cc:
Subject:Re: [ham-amplifiers] 3CX3000F7 10-80m

The Ameritron choke will easily handle 2A?from that tube on CW and SSB.
It is also well placed for minimum coupling.
?
Carl
----- Original Message -----
Sent: Wednesday, November 27, 2019 10:40 AM
Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

That little Ameritron plate choke is screaming for its life :) Very cool amplifier!


On 11/26/2019 6:53 PM, Mike via wrote:
My latest amplifier.
-- 
Please let me quote you for your parts needs!
I offer a discount on Protunes with parts order!
Clark Turner
480-695-2898
    

-- 
From sunny Binningup



Family Businesses:
SP Electrical. 
The Velvet Fox. 
Smart Design Electrical. 
Perth Interiors. 


Re: 3CX3000F7 10-80m

 

Not really. Its rated at 4kv max and 1.5 amp peak. It is the weak link for sure. But if it works it works. Better have a glitch. One arc and its done. In this example its a fuse.:)

Sent from my T-Mobile 4G LTE device

------ Original message------
From: Carl
Date: Thu, Nov 28, 2019 6:25 PM
Cc:
Subject:Re: [ham-amplifiers] 3CX3000F7 10-80m

The Ameritron choke will easily handle 2A?from that tube on CW and SSB.
It is also well placed for minimum coupling.
?
Carl
----- Original Message -----
Sent: Wednesday, November 27, 2019 10:40 AM
Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

That little Ameritron plate choke is screaming for its life :) Very cool amplifier!


On 11/26/2019 6:53 PM, Mike via wrote:
My latest amplifier.
-- 
Please let me quote you for your parts needs!
I offer a discount on Protunes with parts order!
Clark Turner
480-695-2898


Re: 3CX3000F7 10-80m

 

?
Nice amp. I see very few using the F version which is often a real bargain even NOS.
?
Carl

----- Original Message -----
Sent: Tuesday, November 26, 2019 8:53 PM
Subject: [ham-amplifiers] 3CX3000F7 10-80m

My latest amplifier.


Re: 3CX3000F7 10-80m

 

?
The Ameritron choke will easily handle 2A?from that tube on CW and SSB.
It is also well placed for minimum coupling.
?
Carl

----- Original Message -----
Sent: Wednesday, November 27, 2019 10:40 AM
Subject: Re: [ham-amplifiers] 3CX3000F7 10-80m

That little Ameritron plate choke is screaming for its life :) Very cool amplifier!


On 11/26/2019 6:53 PM, Mike via Groups.Io wrote:
My latest amplifier.
-- 
Please let me quote you for your parts needs!
I offer a discount on Protunes with parts order!
Clark Turner
480-695-2898