Re: Traveling Wave Tube Amplifier
Those sound like they may be Bell Labs tubes. 73 – Mike ? Mike B. Feher, N4FS 89 Arnold Blvd. Howell NJ 07731 848-245-9115 ?
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From: [email protected] < [email protected]> On Behalf Of Clint, VE3CMQ Sent: Monday, December 18, 2023 1:22 PM To: [email protected]Subject: [ham-amplifiers] Traveling Wave Tube Amplifier ? Hopefully someone will help me out.? I have 3? LD-4513 Traveling Wave Tube amplifiers.? These I think operate around 2400MHz.? I would like to get some information on them.? A search on Google doesn't seem to come up with anything on this particular device.
73, Clint, VE3CMQ
|
Traveling Wave Tube Amplifier
Hopefully someone will help me out.? I have 3? LD-4513 Traveling Wave Tube amplifiers.? These I think operate around 2400MHz.? I would like to get some information on them.? A search on Google doesn't seem to come up with anything on this particular device.
73, Clint, VE3CMQ
|
Re: AL80B Smells Hot on 10M and 160M
Those are Z5U caps.? They are a poor choice for coupling RF with high current..? No wonder they failed.? Can't believe Alpha would do that. I have repaired several 8410s and I don't even remember those blue caps being used.?
?Really should use a cap that is rated for high RF current.? The idea of using six caps for coupling is just bizarre.? I get that you had them but heck man.? Just order a proper HEC high energy RF cap and be done with it.? The amp will work better and be more
reliable.??
By the way,? Filament voltage on that 8410 should be checked!? They run very high Fil voltage and if your line voltage hits 250 it could pop those tubes.? I know this because one guy kept losing 4cx1000s.? We found he had high line voltage due to the entire
neighborhood being on Solar. In the middle of the day it would hit 260!!? Then Pop the tubes.??
Alpha recommends a buck transformer right in the manual.? Using a variac, I found, ANYTHING over 240 would cause fil voltage to be to HIGH.?
C
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On 12/18/2023 7:47 AM, Jim VE7RF wrote:
The AL-80B? does not use real deal plate block caps, but a pair of disc caps.? ?The disc caps are not RF rated either.? ? Any plate block cap needs to have enough pf? so it's reactance (XC)? is 5% ( or less) at 1.8 mhz.? There is barely any RF current flowing
through a plate blocker on 160m...... but the current through em progressively increases as freq increases.
As a reminder: I just had to replace all three of the 2200 pF/6 kV disc plate blocking caps on my Alpha 8410:
But there was no smell when these blew; they just shorted the high voltage, causing a plate current fault which, fortunately, shut down my amp before any catastrophic damage occurred. These caps apparently shorted out one by one, cracking independently as
each broke down from the high power and voltage (plate voltage in my 8410 is just under 2900VDC). The total capacitance was originally 3 x 2200 pF = 6600 pF; I replaced them with a set of six 1000 pF/10 kV discs I bought a few years back, but unfortunately,
I didn't think to take a pic of the installation. However, note that the way the caps are arranged above, the "outside" of one cap is directly adjacent to the "inside" of another, which means you have the full plate voltage between the capacitors. To make
certain there would be no flashover between capacitors, I therefore spread the replacement caps out evenly but kept the leads all twisted together as shown above and as short as possible so as to minimize any additional inductance. So far, so good, on my Alpha
8410, which has a pair of 4CX1000As in parallel, far more than what a pair of 3-500s will do.
>Correct component would be a pair of HEC? 500 pf HT-50/58,? 7.5 kv? ceramic doorknob caps in parallel .?
> You can buy those cheap, directly from mfj / Ameritron.? That's what's used in the Ameritron?
>AL-1500 / AL-1200 / AL-82.
If I was not in a hurry to get my Alpha back on the air before I missed out on another pileup, I would have ordered HECs instead of using the disc ceramic caps. In the olden days, pre-COVID and pre-Ukraine, you could buy doorknobs of all sizes and voltages
from Russia or even ND2X at dirt-cheap prices and receive them within several weeks (with all sorts of strange and exotic Russian stamps on the boxes). Nowadays, that's neither so easy nor cheap? 8-(
..... all 30 of em test to 15 kv? ( which is the limit of my hi-pot tester that I bought last year from CTR engineering).
High voltage hi-potters are very easy to make and relatively-cheap to boot; just search epay for 10+ kV variable power supplies, perhaps using search terms such as "neon sign power supply", "Tesla coil power supply", or the like. No longer do you need to
spend el mucho buxos for shipping a heavy, old, surplus neon sign transformer; now, the Chinese are selling small, adjustable high voltage power supplies, completely self-contained on a single PC board. I bought one, which consists of a small PC board with
the circuit on it and an onboard transformer, for about $40 a couple years ago; it operates from 12 volts DC. I tested and evaluated the board, then designed and built my own hi-potter. It's fully adjustable from a few hundred volts to over 10 kV, and my hi-potter
includes both a voltmeter as well as a leakage current meter, both mounted on and behind plexiglass to prevent me from touching them while in operation. It actually goes to at least 11 kV and will provide a few tens of microamperes current, which is as much
as you want to have arcing around within a leaking tube, and far more than enough to tell whether it's good or not. It's such a small and cute little gadget that it's difficult to remember that it's more than capable of killing me if I'm not careful with it!
73,
Steve K0XP
|
On Sun, Dec 10, 2023 at 02:46 PM, Dave wrote:
Hello Group, I could use your help!
Looking to pick up a 3-500ZG replacement for my AL-80B.? My choices are:
RF Parts Company: 3-500ZG (6-month warranty). 250$ (China)
DX Engineering: Penta Labs RF Vacuum Tube 3-500ZG (no warranty listed). 300$ (assume China?)
DX Engineering:?Ameritron 3-500Z Replacement Power Tube (All products manufactured by Ameritron have a one-year limited warranty) 360$ (assume China?).
Both vendors have always been reliable for me so my question:
Is the Ameritron tube worth the additional $$ or is it branding?
Is the Penta Tube?worth the additional $$
What would be the best replacement?
(sorry for writing a novel)
Thanks in advance!
73
K5AKM - Dave
Howdy Dave,
Just as an FYI, Henry Radio (yes, they still sell stuff...) has new "Greenstone" 3-500C tubes for sale. They are Chinese (of course), but seem okay, work well, and are "guaranteed"...
I purchased a couple of these a long while back, and they are still running strong. I've run the pair in both my Drake L-4B (that's what they're in now), as well as my Henry 3-KA. They work great, and the price was (I thought) quite reasonable.
Anyway, just another option to consider.
73,
~Alan
W5ARM
|
Re: AL80B Smells Hot on 10M and 160M
On 12/18/2023 7:47 AM, Jim VE7RF wrote:
The AL-80B? does not use real deal plate block caps, but a pair
of disc caps.? ?The disc caps are not RF rated either.? ? Any
plate block cap needs to have enough pf? so it's reactance (XC)?
is 5% ( or less) at 1.8 mhz.? There is barely any RF current
flowing through a plate blocker on 160m...... but the current
through em progressively increases as freq increases.
As a reminder: I just had to replace all three of the 2200 pF/6
kV disc plate blocking caps on my Alpha 8410:
But there was no smell when these blew; they just shorted the
high voltage, causing a plate current fault which, fortunately,
shut down my amp before any catastrophic damage occurred. These
caps apparently shorted out one by one, cracking independently as
each broke down from the high power and voltage (plate voltage in
my 8410 is just under 2900VDC). The total capacitance was
originally 3 x 2200 pF = 6600 pF; I replaced them with a set of
six 1000 pF/10 kV discs I bought a few years back, but
unfortunately, I didn't think to take a pic of the installation.
However, note that the way the caps are arranged above, the
"outside" of one cap is directly adjacent to the "inside" of
another, which means you have the full plate voltage between the
capacitors. To make certain there would be no flashover between
capacitors, I therefore spread the replacement caps out evenly but
kept the leads all twisted together as shown above and as short as
possible so as to minimize any additional inductance. So far, so
good, on my Alpha 8410, which has a pair of 4CX1000As in parallel,
far more than what a pair of 3-500s will do.
>Correct component would be a pair of HEC? 500 pf HT-50/58,?
7.5 kv? ceramic doorknob caps in parallel .?
> You can buy those cheap, directly from mfj / Ameritron.?
That's what's used in the Ameritron?
>AL-1500 / AL-1200 / AL-82.
If I was not in a hurry to get my Alpha back on the air before I
missed out on another pileup, I would have ordered HECs instead of
using the disc ceramic caps. In the olden days, pre-COVID and
pre-Ukraine, you could buy doorknobs of all sizes and voltages
from Russia or even ND2X at dirt-cheap prices and receive them
within several weeks (with all sorts of strange and exotic Russian
stamps on the boxes). Nowadays, that's neither so easy nor cheap?
8-(
..... all 30 of em test to 15 kv? ( which is the limit of my
hi-pot tester that I bought last year from CTR engineering).
High voltage hi-potters are very easy to make and
relatively-cheap to boot; just search epay for 10+ kV variable
power supplies, perhaps using search terms such as "neon sign
power supply", "Tesla coil power supply", or the like. No longer
do you need to spend el mucho buxos for shipping a heavy, old,
surplus neon sign transformer; now, the Chinese are selling small,
adjustable high voltage power supplies, completely self-contained
on a single PC board. I bought one, which consists of a small PC
board with the circuit on it and an onboard transformer, for about
$40 a couple years ago; it operates from 12 volts DC. I tested and
evaluated the board, then designed and built my own hi-potter.
It's fully adjustable from a few hundred volts to over 10 kV, and
my hi-potter includes both a voltmeter as well as a leakage
current meter, both mounted on and behind plexiglass to prevent me
from touching them while in operation. It actually goes to at
least 11 kV and will provide a few tens of microamperes current,
which is as much as you want to have arcing around within a
leaking tube, and far more than enough to tell whether it's good
or not. It's such a small and cute little gadget that it's
difficult to remember that it's more than capable of killing me if
I'm not careful with it!
73,
Steve K0XP
|
Re: AL80B Smells Hot on 10M and 160M
The AL-80B? does not use real deal plate block caps, but a pair of disc caps.? ?The disc caps are not RF rated either.? ? Any plate block cap needs to have enough pf? so it's reactance (XC)? is 5% ( or less) at 1.8 mhz.? There is barely any RF current flowing through a plate blocker on 160m...... but the current through em progressively increases as freq increases.? ? On 10m, there is loads of RF current through a plate blocker.? ?Reason is.... on 160m, the tube C (anode to grid) is directly in parallel with the C1 tune cap.? ?They are in parallel...via the plate block cap? between em.? ?On 160m, the tube C makes up a fraction of the total required C1 value.? On 10m, the tube C makes up most of the C1 tune C.? ?Think of the C1? tune cap as being a tiny variable padder, in parallel? with the tube C.?
?
Correct component would be a pair of HEC? 500 pf HT-50/58,? 7.5 kv? ceramic doorknob caps in parallel .? You can buy those cheap, directly from mfj / Ameritron.? That's what's used in the Ameritron AL-1500 / AL-1200 / AL-82.?
?
What else that will work is higher V rated disc caps.? Typ the higher V rated disc caps? will also handle more RF current.? I just finished testing a mess of new? .01uf ( 10,000 pf)? @ 30 kv? disc caps.? These are HUGE things at 1.125" diam x? 7/16" thick.? ?These are the blue chinese disc caps that I bought from their ebay store.? ?They tested between 9200-9700 pf..... and all 30 of em test to 15 kv? ( which is the limit of my hi-pot tester that I bought last year from CTR engineering).? ?These things handle stupid amounts of RF current.? ?They come in 10/20/30 kv rated.? They are so cheap, and shipping was cheap, so bought 30 of em.? ?So far, so good.? I can't blow em up.?
|
Re: AL80B Smells Hot on 10M and 160M
Scott
My 922 did exactly what you're describing then I had a plate short.? Plate blocking cap had let go... Cracked and got to ground.? That was the smell. It was only on specific bands too.? I reckon you look for hot spots there.
Aaron
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Re: AL80B Smells Hot on 10M and 160M
Jim,
I was not aware of w8ji new site, thanks for posting!
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On Dec 17, 2023, at 5:15 AM, Jim VE7RF < jim.thom@...> wrote:
On 160m it could be the padder caps? for the tune and load caps.? ?On 10m, it could be the plate choke.... and / or? bandswitch contacts.? ?How old is the AL-80B ??? After W8JI left ameritron in 2019, ameritron started winding their own plate chokes. Before that,? W8JI wound all the plate chokes in his shop.? All the chokes wound by ameritron after 2019 are screwed up, with gaps wrong, and? ?too much / too little? q dope slopped down the sides.? Gap at bottom is to close to chassis.? ?Scott has see 8 of em burned up now,,and I know of 4 more.? Some burn up on 10m,? some burn up on 17m, some burn up on 20m.? CTR eng ( W8JI's new business) sells the real deal 3 x section plate chokes for the ameritron amps. On 160m padding, check the wiring to the padders carefully.... as they usually wire from cold end of padders to the bandswitch? and use teflon coated wire.....and if the wire is too close to metal, it will arc right through.?
On some of em,? IF using FT-8 mode, and 17m used, the bandswitch contacts get so hot, they actually lose tension, which increases the? resistance even more =? thermal runaway....and the ceramic actually cracks.?? ?
Lou may well chime in as he has worked on a lot of em.? ?I'll ask scott when I talk to him next, as he has worked on loads of those amps.??
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Re: AL80B Smells Hot on 10M and 160M
On 160m it could be the padder caps? for the tune and load caps.? ?On 10m, it could be the plate choke.... and / or? bandswitch contacts.? ?How old is the AL-80B ???
After W8JI left ameritron in 2019, ameritron started winding their own plate chokes. Before that,? W8JI wound all the plate chokes in his shop.? All the chokes wound by ameritron after 2019 are screwed up, with gaps wrong, and? ?too much / too little? q dope slopped down the sides.? Gap at bottom is to close to chassis.? ?Scott has see 8 of em burned up now,,and I know of 4 more.? Some burn up on 10m,? some burn up on 17m, some burn up on 20m.?
CTR eng ( W8JI's new business) sells the real deal 3 x section plate chokes for the ameritron amps.
On 160m padding, check the wiring to the padders carefully.... as they usually wire from cold end of padders to the bandswitch? and use teflon coated wire.....and if the wire is too close to metal, it will arc right through.?
On some of em,? IF using FT-8 mode, and 17m used, the bandswitch contacts get so hot, they actually lose tension, which increases the? resistance even more =? thermal runaway....and the ceramic actually cracks.??
?
Lou may well chime in as he has worked on a lot of em.? ?I'll ask scott when I talk to him next, as he has worked on loads of those amps.??
|
Re: AL80B Smells Hot on 10M and 160M
Does the tube socket and/or surrounding area show any signs of overheating? Bob W4JFA?
On Sat, Dec 16, 2023, 11:29 PM Scott Hostetler < scott@...> wrote: The Subject is kind of vague but I have a AL-80B. I have no issues on 75-15m.? The 15M Tuned Input is a little?off, maybe they tuned it to 17M.??
?
On 10M when starting tune up process and I get to about 50Watts?I smell a hot smell.
?
40 Watts of Drive,Grid Current is 85 and Plate Current is 350 Output Power is 490W NO SMELL
?
But when I get to 50Watts?I start smelling a HOT, Plastic Smell, the more drive I give it the worst it gets.??@ 50Watts of Drive, Grid Current is 110, Plate is 378 Output is 615W
?
Any Ideas where to start looking for this problem???
?
?
Next Problem on 160M
?
40Watts?of Drive, Grid Current is 70, Plate is 300 Output power is 430W No Smell
?
When I get to 70 Watts of Drive I smell a different?smell, Like a component breaking down.
When I key with 70Watts?of Drive I see 148 of Grid Current that falls to 130 pretty fast.? Plate current holds at 350 with Output power starting at 739 and dropping to 660 pretty fast as well.? It smells almost like your heat does when you turn in on for the first time in the winter but its different?that the 10M smell...
?
Any Ideas?? The other bands work perfect...? Not Issue no matter how long I use it.
?
?
Thanks for you help.? Sorry if descriptions are off, any help will be appreciated.
?
73
K4MDI
Scott
|
AL80B Smells Hot on 10M and 160M
The Subject is kind of vague but I have a AL-80B. I have no issues on 75-15m.? The 15M Tuned Input is a little?off, maybe they tuned it to 17M.??
?
On 10M when starting tune up process and I get to about 50Watts?I smell a hot smell.
?
40 Watts of Drive,Grid Current is 85 and Plate Current is 350 Output Power is 490W NO SMELL
?
But when I get to 50Watts?I start smelling a HOT, Plastic Smell, the more drive I give it the worst it gets.??@ 50Watts of Drive, Grid Current is 110, Plate is 378 Output is 615W
?
Any Ideas where to start looking for this problem???
?
?
Next Problem on 160M
?
40Watts?of Drive, Grid Current is 70, Plate is 300 Output power is 430W No Smell
?
When I get to 70 Watts of Drive I smell a different?smell, Like a component breaking down.
When I key with 70Watts?of Drive I see 148 of Grid Current that falls to 130 pretty fast.? Plate current holds at 350 with Output power starting at 739 and dropping to 660 pretty fast as well.? It smells almost like your heat does when you turn in on for the first time in the winter but its different?that the 10M smell...
?
Any Ideas?? The other bands work perfect...? Not Issue no matter how long I use it.
?
?
Thanks for you help.? Sorry if descriptions are off, any help will be appreciated.
?
73
K4MDI
Scott
|
I do love FM……Fleetwood Mac, that is ! ?
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From: [email protected] <[email protected]> On Behalf Of Adrian Fewster
Sent: Thursday, December 14, 2023 11:06 AM
To: [email protected]
Subject: Re: [ham-amplifiers] Replacement 3-500ZG? On Tue, Dec 12, 2023 at 02:22 AM, John Sparkes wrote: You’re not the drummer in Fleetwood Mac, are you Mick ?? ? John VK6JX ?
Like this guy ? One of my favorite tracks, been a fan for 50 years
|
12 KW CCS ON 160-15M...USING THE 3CX-6000A7...Part 8.
Here is Part 8. The vac tune cap is installed vertically. The vac load cap is also installed vertically. And both have right angle drives. The massive model 90 bandswitch, made by multi-tech industries is also installed.
The bandswitch is huge at 9" tall x 7" across. Contacts rated at 40 amps @ 20 kv. That '40 amp' rating is at 60 hz... and NOT RF freqs. Scott modified the switch by adding another identical set of contacts on the other side of the ceramic wafer, then paralleling the contacts. So it's now a 80 amp switch. It's a progressively shorting switch, so all un-used taps are shunted out.
https://www.youtube.com/watch?v=ngYUTerziyY
?
|
No, but I get all the fame!
At 09:22 PM 12/12/2023, you wrote:
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You’re not the drummer in
Fleetwood Mac, are you Mick ??
?
John VK6JX
?
From: [email protected] <[email protected]>
On Behalf Of mfle2001
Sent: Tuesday, December 12, 2023 6:12 PM
To: [email protected]
Subject: Re: [ham-amplifiers] Replacement 3-500ZG
?
I ordered a pair from Penta Labs a year or so ago, very reasonable price
with shipping to VK and amazingly well packed, so far so good in my
TL922.
Mike
VK2AMF.
At 09:37 AM 11/12/2023, you wrote:
- I have had good service from RF parts.?? Ups broke the tube in
shipping and it was replaced no issue
- Brian
- On Sun, Dec 10, 2023, 1:26 p.m. DupyRail
<andytron434@...>
wrote:
- FWIW, contact Tom, W8JI at CTR Engineering.?? From what I
understand he has tubes F/S that are tested by him to make sure they are
working.
- 73?? Andy?? K9ATX
- On 12/10/2023 12:03 PM, Dave wrote:
- Hello Group, I could use your help!
- Looking to pick up a 3-500ZG replacement for my AL-80B.?? My
choices are:
- RF Parts Company: 3-500ZG (6-month warranty). 250$ (China)
- DX Engineering: Penta Labs RF Vacuum Tube 3-500ZG (no warranty
listed). 300$ (assume China?)
- DX Engineering:? Ameritron 3-500Z Replacement Power Tube (All
products manufactured by Ameritron have a one-year limited warranty) 360$
(assume China?).
- Both vendors have always been reliable for me so my
question:
- Is the Ameritron tube worth the additional $$ or is it
branding?
- Is the Penta Tube? worth the additional $$
- What would be the best replacement?
- (sorry for writing a novel)
- Thanks in advance!
- 73
- K5AKM - Dave
- ?
--
?
"Where the Old Soo crossed the New
Soo"
?
Duplainville,
Wisconsin
?
?
Web page:
?
?
Youtube Channel:
-
- Mike Fleetwood
- Canberra Australia and Sidcup UK.
- Worldwide email address is:?????
mfleetwood@...
Mike Fleetwood
Canberra Australia and Sidcup UK.
Worldwide email address
is:?????
mfleetwood@...
|
No, but I get all the fame!
Mike VK2AMF?
On Thu, 14 Dec 2023, 14:06 Adrian Fewster, < vk4tux@...> wrote: On Tue, Dec 12, 2023 at 02:22 AM, John Sparkes wrote:
You’re not the drummer in Fleetwood Mac, are you Mick ??
?
John VK6JX
?
Like this guy ? One of my favorite tracks, been a fan for 50 years
|
Re: Ten-Tec Centurion Parts Needed
Hi Ron,
I emailed you directly asking the price of the transformer. ? I don't know if you received it.
My email is good on QRZ.com.??? ....Bill K3HZP
|
Re: Ameritron AL-80 (Not A or B)
What do you guys think about the correction kit sold for AL-80B?
73,?
Tony
|
You’re not the drummer in Fleetwood Mac, are you Mick ?? ? John VK6JX ?
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From: [email protected] <[email protected]> On Behalf Of mfle2001
Sent: Tuesday, December 12, 2023 6:12 PM
To: [email protected]
Subject: Re: [ham-amplifiers] Replacement 3-500ZG? I ordered a pair from Penta Labs a year or so ago, very reasonable price with shipping to VK and amazingly well packed, so far so good in my TL922.
Mike
VK2AMF.
At 09:37 AM 11/12/2023, you wrote:
I have had good service from RF parts.?? Ups broke the tube in shipping and it was replaced no issue
Brian
On Sun, Dec 10, 2023, 1:26 p.m. DupyRail <andytron434@...> wrote: FWIW, contact Tom, W8JI at CTR Engineering.?? From what I understand he has tubes F/S that are tested by him to make sure they are working.
73?? Andy?? K9ATX
On 12/10/2023 12:03 PM, Dave wrote:
Hello Group, I could use your help! Looking to pick up a 3-500ZG replacement for my AL-80B.?? My choices are: RF Parts Company: 3-500ZG (6-month warranty). 250$ (China) DX Engineering: Penta Labs RF Vacuum Tube 3-500ZG (no warranty listed). 300$ (assume China?) DX Engineering:? Ameritron 3-500Z Replacement Power Tube (All products manufactured by Ameritron have a one-year limited warranty) 360$ (assume China?). Both vendors have always been reliable for me so my question: Is the Ameritron tube worth the additional $$ or is it branding? Is the Penta Tube? worth the additional $$ What would be the best replacement? (sorry for writing a novel) Thanks in advance! 73 K5AKM - Dave
? -- ? "Where the Old Soo crossed the New Soo" ? Duplainville, Wisconsin ? ? Web page:? ? ? Youtube Channel:?
Mike Fleetwood
Canberra Australia and Sidcup UK.
Worldwide email address is:????? mfleetwood@...
|
I ordered a pair from Penta Labs a year or so ago, very reasonable price
with shipping to VK and amazingly well packed, so far so good in my
TL922.
Mike
VK2AMF.
At 09:37 AM 11/12/2023, you wrote:
toggle quoted message
Show quoted text
I have had good service from RF
parts.?? Ups broke the tube in shipping and it was replaced no
issue
Brian
On Sun, Dec 10, 2023, 1:26 p.m. DupyRail
<andytron434@...>
wrote:
- FWIW, contact Tom, W8JI at CTR Engineering.?? From what I
understand he has tubes F/S that are tested by him to make sure they are
working.
- 73?? Andy?? K9ATX
- On 12/10/2023 12:03 PM, Dave wrote:
- Hello Group, I could use your help!
- Looking to pick up a 3-500ZG replacement for my AL-80B.?? My
choices are:
- RF Parts Company: 3-500ZG (6-month warranty). 250$ (China)
- DX Engineering: Penta Labs RF Vacuum Tube 3-500ZG (no warranty
listed). 300$ (assume China?)
- DX Engineering:? Ameritron 3-500Z Replacement Power Tube (All
products manufactured by Ameritron have a one-year limited warranty) 360$
(assume China?).
- Both vendors have always been reliable for me so my question:
- Is the Ameritron tube worth the additional $$ or is it branding?
- Is the Penta Tube? worth the additional $$
- What would be the best replacement?
- (sorry for writing a novel)
- Thanks in advance!
- 73
- K5AKM - Dave
--
- "Where the Old Soo crossed the New Soo"
- Duplainville, Wisconsin
- Web page:?
- Youtube Channel:?
Mike Fleetwood
Canberra Australia and Sidcup UK.
Worldwide email address
is:?????
mfleetwood@...
|
Re: Ameritron AL-80 (Not A or B)
Bob,
45-50 watts in for 350-400 out
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Jim, I have one of these amps. With low drive from the exciter, the "load" will often end up all the way left/meshed. That's why I asked the op that.
Bob W4JFA?
On Mon, Dec 11, 2023, 11:50 AM Jim VE7RF < jim.thom@...> wrote:
It appears the padder(s) are not being switched in on 40-80-160m.? BUT u have the issue on all bands.? It's as though the load cap isn't even in the circuit, or lousy tank coil coil connections.
-- 73 Nick KC0YKO
|
Alan - W5ARM
Mike
Bob
Bill K3HZP
Nick Jones KC0YKO