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:
|
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
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Re: Ten-Tec Centurion Parts Needed
Sorry, I don't have any transformers for the 30L-1. Tom
Hi Tom,? I am looking for a transformer for a 30L1 amp that I am repairing for a SK's widow.? The current one appears to have a short and blows fuses.? You mentioned having Collins parts.?? Any suggestions?
73,? Bill K3HZP
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Collins transformers for the 30L-1
Bill K3HZP,
Contact Heyboer, they have all the PWDahl specs and can build a PWDP13170 cheaper than a rewind. They did a Globe King 500A modulation transformer for me and it's great.
73 Bill N4LG
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Show quoted text
At 12:29 PM 12/10/2023, Nick Jones KC0YKO wrote: Nationwide radio has a good selection of Collins transformers but it looks like they currently do not have one for the 30L-1.
Peter Dahl makes a replacement p/n
PWDP13170
--
73 Nick KC0YKO
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Re: Ten-Tec Centurion Parts Needed
Nationwide radio has a good selection of Collins transformers but it looks like they currently do not have one for the 30L-1.
Peter Dahl makes a replacement p/n?
PWDP13170
--
73 Nick KC0YKO
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Re: Ten-Tec Centurion Parts Needed
Hi Tom,? I am looking for a transformer for a 30L1 amp that I am repairing for a SK's widow.? The current one appears to have a short and blows fuses.? You mentioned having Collins parts.?? Any suggestions?
73,? Bill K3HZP
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Re: Ameritron AL-80 (Not A or B)
Thanks for all of the reply. I will check the connections within the tank circuit. The band switch looks OK but I will investigate closer. Band switch is in the correct position when testing.
--
73 Nick KC0YKO
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Re: Ameritron AL-80 (Not A or B)
Is the band switch in good condition, in the correct position?
On Sunday, December 10, 2023 at 09:41:10 AM EST, Nick Jones KC0YKO <kc0yko@...> wrote:
All,
Question for the group. I am working on an Ameritron AL-80 (not A or B). When tuning it up I run out of load. I max the load cap out at zero on all bands. (fully meshed/max capacitance). It behaves the same on a two different dummy loads so I believe it to be an issue with the amp. Before I add another doorknob across the load cap, I figured I would ask the group for other ideas.
--
73 Nick KC0YKO
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Re: Ameritron AL-80 (Not A or B)
Nick,it seems as though you may have a poor connection somewhere inside the realm of the tank circuit. ?This could be at the band switch, the connections of the coils to the variables or just about anywhere, so make sure of all mechanical and soldered connections. ?Above 4 meters there are no padding cap issues so it’s got to be something like that. ?Also be sure there is no slippage on any of the connections to the variable capacitor shafis! ?Good luck
On Sunday, December 10, 2023, 9:41 AM, Nick Jones KC0YKO <kc0yko@...> wrote: All,
Question for the group. I am working on an Ameritron AL-80 (not A or B). When tuning it up I run out of load. I max the load cap out at zero on all bands. (fully meshed/max capacitance). It behaves the same on a two different dummy loads so I believe it to be an issue with the amp. Before I add another doorknob across the load cap, I figured I would ask the group for other ideas.
--
73 Nick KC0YKO
|
Ameritron AL-80 (Not A or B)
All,
Question for the group. I am working on an Ameritron AL-80 (not A or B). When tuning it up I run out of load. I max the load cap out at zero on all bands. (fully meshed/max capacitance). It behaves the same on a two different dummy loads so I believe it to be an issue with the amp. Before I add another doorknob across the load cap, I figured I would ask the group for other ideas.
--
73 Nick KC0YKO
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Re: Ten-Tec Centurion Parts Needed
“Although it’s a handsome looking amp it’s certainly not the best performer in its class. ?It lacks inductance on 160 and the tank isn’t so good on 15 and 10”. ? So true, Louis. As Jim VE7RF also told me, my Emtron DX-2SP had the exact same issues on the low bands, but especially on 15, 12 and 10m. After a few years of 1200-1500W FT8 operation, my 10m and 15/12m tank coil tap flexible soldered silver plated conductors were black and the two connections to the tank coil had gone…..bad. I re-made these two connections with 8mm flat silver plated copper conductor, held in place with tightening brass screws onto the tank coil and silver solder to make sure. Luckily, my band switch was unaffected by the high circulating currents. I added inductance on the toroidal tank inductor by moving the tap an additional 3 turns for 80m. This improved the efficiency up to around 60% (was below 40%) on 80m. Then I added some fixed loading capacitance on 160m which raised the efficiency on 160m from around 30% up to 50%. All of our Ham multi-band amps have these same problems, but they are solvable with a little help from the experts on here. ? My Emtron is now working well on all bands. ? Cheers, ? John VK6JX ?
toggle quoted message
Show quoted text
From: [email protected] <[email protected]> On Behalf Of Louis Parascondola via groups.io
Sent: Sunday, December 10, 2023 1:10 PM
To: [email protected]
Subject: Re: [ham-amplifiers] Ten-Tec Centurion Parts Needed? TenTec buit?their own variable capacitors. ?So their plates are unlike any others. ?I have some plates and if you want you?ship me the cap I’ll rebuild it for you. ?I should have a few plates left. ?Although it’s a handsome looking amp it’s certainly not the best performer in its class. ?It lacks inductance on 160 and the tank isn’t so hood on 15 and 10. ?
? On Saturday, December 9, 2023, 6:51 PM, Tom Hess <Tomhess8@...> wrote: I have a lot of parts for amplifiers and stuff. I handle estates for the local ham club and have? processed estates for several Collins Radio engineers. They collected lots of parts over the years. I don't have any experience with the Centurion, so I don't know what your parts look like. Please send a photo of the switch and specs?for the capacitor - size, value, voltage. ? On Sat, Dec 9, 2023 at 9:42?AM Omni <selcor@...> wrote: I have recently acquired a Ten-Tec Centurion model 422 that is in very nice condition, but has a blown up bandswitch and the plate tuning capacitor was arced.? I might be able to salvage the capacitor, but the bandswich will need to be rebuilt or replaced.? If anyone has a switch/parts and/or a capacitor please contact me off list to let me know what you have.
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Re: Ten-Tec Centurion Parts Needed
TenTec buit?their own variable capacitors. ?So their plates are unlike any others. ?I have some plates and if you want you?ship me the cap I’ll rebuild it for you. ?I should have a few plates left. ?Although it’s a handsome looking amp it’s certainly not the best performer in its class. ?It lacks inductance on 160 and the tank isn’t so hood on 15 and 10. ?
On Saturday, December 9, 2023, 6:51 PM, Tom Hess <Tomhess8@...> wrote: I have a lot of parts for amplifiers and stuff. I handle estates for the local ham club and have? processed estates for several Collins Radio engineers. They collected lots of parts over the years. I don't have any experience with the Centurion, so I don't know what your parts look like. Please send a photo of the switch and specs?for the capacitor - size, value, voltage. Tom KD0HF On Sat, Dec 9, 2023 at 9:42?AM Omni < selcor@...> wrote: I have recently acquired a Ten-Tec Centurion model 422 that is in very nice condition, but has a blown up bandswitch and the plate tuning capacitor was arced.? I might be able to salvage the capacitor, but the bandswich will need to be rebuilt or replaced.? If anyone has a switch/parts and/or a capacitor please contact me off list to let me know what you have.
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Re: Potter & Brumfield Sensitive Plate Circuit Relays
Hi ALL,
?
I have amongst my Henry Amps a 3K-A. (My 3K-A was manufactured in 1972 and still works well.)? It has the plate current relay in the B- lead to trip on over current above 1A.
?
?
5.2? ADJUSTMENT OF THE OVERLOAD RELAY
?
A low voltage, variable, metered DC supply of 1 amp is needed for this adjustment. The 3K-A should stay of f during this adjustment.
?
Connect the DC supply to the slider of R103 and to ground and increase the current of the supply to 1 amp.?? RYlOl should trip.?? If the relay does not trip, adjust
Rl03 until the relay trips at about 1 amp. When adjusting the overload relay, reset and check the overload current several times to get an average
setting.? RI03 should be about 3-4ohms.
?
If you download a copy of the 3K-A schematic and manual it explains how the relay works and how to calibrate the trip point.
?
In my opinion it would have been better served as a trip for the grid current.
?
Other amps and devices may have also used this method for protection.
?
?
73
?
Walt
KR4HV
?
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Re: Ten-Tec Centurion Parts Needed
I have a lot of parts for amplifiers and stuff. I handle estates for the local ham club and have? processed estates for several Collins Radio engineers. They collected lots of parts over the years. I don't have any experience with the Centurion, so I don't know what your parts look like. Please send a photo of the switch and specs?for the capacitor - size, value, voltage. Tom KD0HF
On Sat, Dec 9, 2023 at 9:42?AM Omni < selcor@...> wrote: I have recently acquired a Ten-Tec Centurion model 422 that is in very nice condition, but has a blown up bandswitch and the plate tuning capacitor was arced.? I might be able to salvage the capacitor, but the bandswich will need to be rebuilt or replaced.? If anyone has a switch/parts and/or a capacitor please contact me off list to let me know what you have.
|
Re: Potter & Brumfield Sensitive Plate Circuit Relays
Thanks Steve. I do not any of the power supply, just the RF deck, but did work it and it pulls in at just under 22vdc
--
73 Nick KC0YKO
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Re: Potter & Brumfield Sensitive Plate Circuit Relays
Thanks Chuck. I was clearly over complicating this just because I did not recognize the "plate circuit relay" terminology. You were correct, I rolled the variable power supply up and it pulled in at just under 22vdc
--
73 Nick KC0YKO
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Re: Potter & Brumfield Sensitive Plate Circuit Relays
Hal, Thanks for the reply. I do not have the power supply, just the RF deck.?
--
73 Nick KC0YKO
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Re: Potter & Brumfield Sensitive Plate Circuit Relays
Perhaps that relay was used in that application in an effort to
reduce the voltage/current to operate it to low values, such as
from a later-model (but older) transceiver with limited T/R relay
switching capability. Also, if there is a power supply used in the
amp for that relay, look at the output filter capacitor to get an
idea of the maximum voltage that was applied to operate the relay.
If that relay really is a "Sensitive Plate Circuit Relay", you
might find a miniature adjustment mounted on the armature by which
the actual sensitivity was adjusted. Sometimes, that adjustment
would have a very small indication plate on which the adjustment
range was mentioned in milliamperes.
If you apply power from an external adjustable power supply to
try to find what voltage/current used to actuate the relay, I
would first apply that power through an external current-limiting
resistor so as to limit the external voltage/current to something
most likely used to actuate the relay; otherwise, you could burn
out the relay coil very easily. Typically, such relays operated
with just a few milliamperes but as much as 10 - 30 VDC. That
"high" voltage was common because those relays were in the plate
circuits of receiving-type tubes passing only a few mils at a
hundred or more volts.
In the olden days, we hams used to use such relays to detect and
protect the sensitive screen or control grids of tubes from the
ravages of overcurrent. Less commonly, they could also be used to
detect overcurrent of cathode or plate current by connecting them
across resistive voltage dividers.
Steve,
K0XP
On 12/9/2023 9:06 AM, Nick Jones KC0YKO
wrote:
All, I have an old homebrew RF deck that the T/R rely is a Potter
& Brumfield LM11-2500. I can't find what the coil voltage is.
In the 1954 P&B catalog the LM series is titled?Sensitive
Plate Circuit Relays and only list coil resistance and pull MA
ratings. What was the typical application for a Sensitive Plate
Circuit Relay, and what voltage energized the coil? Not sure why I
am struggling to understand this but do not recognize the
Sensitive Plate Circuit Relay application. Thanks Nick
--
See my QRZ.com page at
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Re: Potter & Brumfield Sensitive Plate Circuit Relays
Dear Nick,
?
My GUESS is the P&B magnet is 24 to 28 Vdc.
?
However, if you trace the wiring to the coil, back to
the power supply, you may there deduce the coil voltage by
energizing the xfmr primaries.
?
Hal
W4HBM
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Re: Potter & Brumfield Sensitive Plate Circuit Relays
Years ago the coil of a plate circuit relay was in series with the plate of a vacuum tube set up to conduct at the pull in current when the tube was biased on.? Using ohms law, 0.009 A X 2500 ohms = 22.5V to “pull in” if you measured the voltage across the coil. ?Vacuum tubes were used just like transistors today to energize relays. ? -Chuck K1KW ?
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Show quoted text
From: [email protected] [mailto:[email protected]] On Behalf Of Nick Jones KC0YKO
Sent: Saturday, December 09, 2023 12:06 PM
To: [email protected]
Subject: [ham-amplifiers] Potter & Brumfield Sensitive Plate Circuit Relays ? All, I have an old homebrew RF deck that the T/R rely is a Potter & Brumfield LM11-2500. I can't find what the coil voltage is. In the 1954 P&B catalog the LM series is titled?Sensitive Plate Circuit Relays and only list coil resistance and pull MA ratings. What was the typical application for a Sensitive Plate Circuit Relay, and what voltage energized the coil? Not sure why I am struggling to understand this but do not recognize the Sensitive Plate Circuit Relay application. Thanks Nick
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Tom Hess
Nick Jones KC0YKO
Bill K3HZP
HaL Mandel