And since 3-500Z tubes are zero-bias ....
73 Jim N6OTQ
And keep in mind
I make zero, zip, nada off tubes my customers purchase and drop ship to
me.
So my statement is truly un biased.
On 2024-05-18 13:11, W7WRX wrote:
> The best appears to be from CTR engineering.? There are two plants
> that make 3-500 tubes in china. These are the best of the two.? They
> are fully Hi pot tested and guaranteed.? ?Mine have been rock solid.
>
>? 811A 572B 3-500Z Vacuum Tubes For Sale ¨C CTR Engineering, Inc
> () [1]
>
>? I have had very bad luck with Penta.? Over and over failed or gassy
> tubes out of the box.? I ended up just getting a refund, They were
> nice to deal with, no trouble.? I was told they likely just got a bad
> batch.? Maybe they are better now. This was a year or two ago.
>
>? C
>
> -------------------------
>
> From: [email protected] <[email protected]> on behalf of
> Joe - W7RKN via <w7rkn.7=[email protected]>
> Sent: Saturday, May 18, 2024 9:52 AM
> To: [email protected] <[email protected]>
> Subject: [ham-amplifiers] 3-500 tubes
>
> It appears I have a shorted 3-500Z tube in my AL-82 amplifier.
>
> It also appears that right now the 3-500Z or ZG tubes are unobtainium.
>
>
> Sellers on eBay are selling new Penta tubes for a ridiculous amount of
> money.
>
> Are Penta tubes any good?
>
> Perhaps I should ask first, who has 3-500¡¯s for sale?
>
> I am going to replace the T/R relay in the amp while I have it
> open¡.Been a weak component in the amplifier since it was new.? Been
> replaced twice now and the amp is only 4 years old.
>
> A friend who is? an amplifier guru is going to look into building an
> external, plug in, relay setup for me.? Then I could go to a vacuum
> relay and my T/R relay issues would be over!? Just to be on the safe
> side, I just purchased 3 relays from Ameritron (MFJ) to have when they
> are no longer doing business.? If I do the relay modification, the
> Ameritron relays should sell fairly quickly as it appears all their
> high power amps use the same relay.
>
> Thanks in advance, for any questions answered!
>
> Joe ¨C W7RKN
>
>
> Links:
> ------
> [1]
> [2] /g/ham-amplifiers/message/40383
> [3] /mt/106173952/8135091
> [4] /g/ham-amplifiers/post
> [5] /g/ham-amplifiers/editsub/8135091
> [6]
> /g/ham-amplifiers/leave/12941173/8135091/773995006/xyzzy
|
And keep in mind
I make zero, zip, nada off tubes my customers purchase and drop ship to me.
So my statement is truly un biased.
toggle quoted message
Show quoted text
On 2024-05-18 13:11, W7WRX wrote: The best appears to be from CTR engineering. There are two plants
that make 3-500 tubes in china. These are the best of the two. They
are fully Hi pot tested and guaranteed. Mine have been rock solid.
811A 572B 3-500Z Vacuum Tubes For Sale ¨C CTR Engineering, Inc
(ctrengineeringinc.com) [1]
I have had very bad luck with Penta. Over and over failed or gassy
tubes out of the box. I ended up just getting a refund, They were
nice to deal with, no trouble. I was told they likely just got a bad
batch. Maybe they are better now. This was a year or two ago.
C
-------------------------
From: [email protected] <[email protected]> on behalf of
Joe - W7RKN via groups.io <w7rkn.7@...>
Sent: Saturday, May 18, 2024 9:52 AM
To: [email protected] <[email protected]>
Subject: [ham-amplifiers] 3-500 tubes
It appears I have a shorted 3-500Z tube in my AL-82 amplifier.
It also appears that right now the 3-500Z or ZG tubes are unobtainium.
Sellers on eBay are selling new Penta tubes for a ridiculous amount of
money.
Are Penta tubes any good?
Perhaps I should ask first, who has 3-500¡¯s for sale?
I am going to replace the T/R relay in the amp while I have it
open¡.Been a weak component in the amplifier since it was new. Been
replaced twice now and the amp is only 4 years old.
A friend who is an amplifier guru is going to look into building an
external, plug in, relay setup for me. Then I could go to a vacuum
relay and my T/R relay issues would be over! Just to be on the safe
side, I just purchased 3 relays from Ameritron (MFJ) to have when they
are no longer doing business. If I do the relay modification, the
Ameritron relays should sell fairly quickly as it appears all their
high power amps use the same relay.
Thanks in advance, for any questions answered!
Joe ¨C W7RKN
Links:
------
[1]
[2] /g/ham-amplifiers/message/40383
[3] /mt/106173952/8135091
[4] /g/ham-amplifiers/post
[5] /g/ham-amplifiers/editsub/8135091
[6] /g/ham-amplifiers/leave/12941173/8135091/773995006/xyzzy
|
I have used thousands of 3-500zg penta tubes in customers pa¡¯s. Not once have I had an issue or have any customers reported an issue.
But I was putting new tubes into pa¡¯s that I had gone through and made right. You can¡¯t just plug tubes into a pa that could have any issue.
The 572b tubes have issues now and then, but that¡¯s a factory issue. Penta does an excellent job pre testing, but sometimes the 572b tube can still have an issue.
Why I have the customer drop ship the tubes to me to test in their amp prior to shipping to them. Rather it happen here and not at their qth.
If you have a problem with a penta tube they just replace it. Unless obvious abuse. They do t make you Jim through hoops.
73
toggle quoted message
Show quoted text
On 2024-05-18 13:40, Jim VE7RF wrote: On Sat, May 18, 2024 at 09:11 PM, W7WRX wrote:
The best appears to be from CTR engineering. There are two plants
that make 3-500 tubes in china. These are the best of the two. They
are fully Hi pot tested and guaranteed. Mine have been rock solid.
811A 572B 3-500Z Vacuum Tubes For Sale - CTR Engineering, Inc
(ctrengineeringinc.com) [1]
I have had very bad luck with Penta. Over and over failed or gassy
tubes out of the box. I ended up just getting a refund, They were
nice to deal with, no trouble. I was told they likely just got a
bad batch. Maybe they are better now. This was a year or two ago. CTR gets his 3-500Z's from the exact same chinese factory as
Pentalabs....and also RF parts. These are the ones with the white
bases. Factory #2 is junk, with a 70% failure rate....and those all
have brown bases.
Even tubes from the good factory all just 1 kv hi-pot test between
grid and cathode. (Eimac's are typ 5 kv from grid to cathode...and 16
kv from anode to grid). The good chinese tubes have higher grid to
cathode C vs eimac. It appears the chinese tubes have spaced the
grid closer to the cathode vs eimac.
A month ago, everybody and their dog got a severe bad batch of chinese
572B's..... like the entire production was screwed up...... but the
572B is another, all together scenario.
Links:
------
[1]
[2] /g/ham-amplifiers/message/40384
[3] /mt/106173952/8135091
[4] /g/ham-amplifiers/post
[5] /g/ham-amplifiers/editsub/8135091
[6] /g/ham-amplifiers/leave/12941173/8135091/773995006/xyzzy
|
On Sat, May 18, 2024 at 09:11 PM, W7WRX wrote:
The best appears to be from CTR engineering.? There are two plants that make 3-500 tubes in china. These are the best of the two.? They are fully Hi pot tested and guaranteed.? ?Mine have been rock solid.
?
?
I have had very bad luck with Penta.? Over and over failed or gassy tubes out of the box.? I ended up just getting a refund, They were nice to deal with, no trouble.? I was told they likely just got a bad batch.? Maybe they are better now. This was a year or two ago.?
CTR gets his 3-500Z's from the exact same chinese factory as Pentalabs....and also RF parts.? ?These are the ones with the white bases.? ?Factory #2 is junk, with a 70% failure rate....and those all have brown bases.?
Even tubes from the good factory all? just 1 kv hi-pot test? between grid and cathode.? (Eimac's are typ 5 kv from grid to cathode...and 16 kv from anode to grid).? ?The good chinese tubes have higher grid to cathode C? vs? eimac.? It appears the chinese tubes? have spaced the grid closer to the cathode vs eimac.?
?
A month ago, everybody and their dog got a severe bad batch of chinese 572B's..... like the entire production was screwed up...... but the 572B is another, all together scenario.?
|
The best appears to be from CTR engineering.? There are two plants that make 3-500 tubes in china. These are the best of the two.? They are fully Hi pot tested and guaranteed.? ?Mine have been rock solid.
I have had very bad luck with Penta.? Over and over failed or gassy tubes out of the box.? I ended up just getting a refund, They were nice to deal with, no trouble.? I was told they likely just got a bad batch.? Maybe they are better now. This was a year or
two ago.?
C
toggle quoted message
Show quoted text
It appears I have a shorted 3-500Z tube in my AL-82 amplifier.
?
It also appears that right now the 3-500Z or ZG tubes are
unobtainium.
?
Sellers on eBay are selling new Penta tubes for a ridiculous amount of money.
?
Are Penta tubes any good?
?
Perhaps I should ask first, who has 3-500¡¯s for sale?
?
I am going to replace the T/R relay in the amp while I have it open¡.Been a weak component in the amplifier since it was new.?
Been replaced twice now and the amp is only 4 years old.
A friend who is?
an amplifier guru is going to look into building an external, plug in, relay setup for me.?
Then I could go to a vacuum relay and my T/R relay issues would be over!?
Just to be on the safe side, I just purchased 3 relays from
Ameritron (MFJ) to have when they are no longer doing business.?
If I do the relay modification, the Ameritron relays should sell fairly quickly as it appears all their high power amps use the same relay.
?
Thanks in advance, for any questions answered!
?
Joe ¨C W7RKN
|
On Sat, May 18, 2024 at 06:52 PM, Joe - W7RKN wrote:
It appears I have a shorted 3-500Z tube in my AL-82 amplifier.
?
It also appears that right now the 3-500Z or ZG tubes are unobtainium.
?
Sellers on eBay are selling new Penta tubes for a ridiculous amount of money.
?
Are Penta tubes any good?
?
Perhaps I should ask first, who has 3-500¡¯s for sale?
?
I am going to replace the T/R relay in the amp while I have it open¡.Been a weak component in the amplifier since it was new.? Been replaced twice now and the amp is only 4 years old.
A friend who is? an amplifier guru is going to look into building an external, plug in, relay setup for me.? Then I could go to a vacuum relay and my T/R relay issues would be over!? Just to be on the safe side, I just purchased 3 relays from Ameritron (MFJ) to have when they are no longer doing business.? If I do the relay modification, the Ameritron relays should sell fairly quickly as it appears all their high power amps use the same relay.
?
Thanks in advance, for any questions answered!
?
Joe ¨C W7RKN
###? Cheapest price is HARBACH ELECTRONICS.....which re-opens on May 20....at the stroke of midnight EST.
$275.00? each.? ?$550.00? for a matched pair.? ?Free shipping, no tax.
?
These are the good ones, with the white base.?
?
?
?
|
Not sure why so many are freaking out about the closure and parts availability. All of the parts they carry are still in production.
Most of them have other part options that will work in their place.
Ameritron will also be around for at least another year .
73
Scott
toggle quoted message
Show quoted text
|
On Sat, May 18, 2024 at 08:31 PM, Colin Kaminski wrote:
<I needed up adding a QSK-5 instead. There is at least one more on the classifieds. I don¡¯t know how you got ahold of Ameritron. I can¡¯t get through.?
<Colin -?
phone all three BOTH numbers on their contact list.? ?I got through to em....twice, 2 days ago.?
ameritron ?1-662-323-8211
MFJ Enterprises Inc:
Toll Free:?1-800-647-1800
?
MFJ / Vectronics / Mirage:
Phone#:?1-662-323-5869
Tech Support/Part Orders Phone#: 1-662-323-0549
?
|
Un obtanium ? What makes you think and then say that ?
Penta and all the others are Chinese. Ones with the white ceramic base all come from the same factory, and are from the better of the two factories over there.
Yes penta¡¯s are good, also excellent customer service.
73 Scott
MOn 2024-05-18 10:52, Joe - W7RKN wrote:
toggle quoted message
Show quoted text
It appears I have a shorted 3-500Z tube in my AL-82 amplifier.
It also appears that right now the 3-500Z or ZG tubes are unobtainium.
Sellers on eBay are selling new Penta tubes for a ridiculous amount of
money.
Are Penta tubes any good?
Perhaps I should ask first, who has 3-500¡¯s for sale?
I am going to replace the T/R relay in the amp while I have it
open¡.Been a weak component in the amplifier since it was new. Been
replaced twice now and the amp is only 4 years old.
A friend who is an amplifier guru is going to look into building an
external, plug in, relay setup for me. Then I could go to a vacuum
relay and my T/R relay issues would be over! Just to be on the safe
side, I just purchased 3 relays from Ameritron (MFJ) to have when they
are no longer doing business. If I do the relay modification, the
Ameritron relays should sell fairly quickly as it appears all their
high power amps use the same relay.
Thanks in advance, for any questions answered!
Joe ¨C W7RKN
Links:
------
[1] /g/ham-amplifiers/message/40377
[2] /mt/106173952/8135091
[3] /g/ham-amplifiers/post
[4] /g/ham-amplifiers/editsub/8135091
[5] /g/ham-amplifiers/leave/12941173/8135091/773995006/xyzzy
|
I needed up adding a QSK-5 instead. There is at least one more on the classifieds. I don¡¯t know how you got ahold of Ameritron. I can¡¯t get through.?
Colin -?
|
It appears I have a shorted 3-500Z tube in my AL-82 amplifier. ? It also appears that right now the 3-500Z or ZG tubes are unobtainium. ? Sellers on eBay are selling new Penta tubes for a ridiculous amount of money. ? Are Penta tubes any good? ? Perhaps I should ask first, who has 3-500¡¯s for sale? ? I am going to replace the T/R relay in the amp while I have it open¡.Been a weak component in the amplifier since it was new.? Been replaced twice now and the amp is only 4 years old. A friend who is? an amplifier guru is going to look into building an external, plug in, relay setup for me.? Then I could go to a vacuum relay and my T/R relay issues would be over!? Just to be on the safe side, I just purchased 3 relays from Ameritron (MFJ) to have when they are no longer doing business.? If I do the relay modification, the Ameritron relays should sell fairly quickly as it appears all their high power amps use the same relay. ? Thanks in advance, for any questions answered! ? Joe ¨C W7RKN
|
Re: 12 KW CCS ON 160-15M...USING THE 3CX-6000A7... PART 15
On Wed, Apr 24, 2024 at 12:38 PM, <tardivat@...> wrote:
<Hi Jim
<Are those HT57's the USA made ones or the Chinese ones. I notice that Ebay seems to flooded with fake HT57's or has High Energy moved their factory to China like everything else these days?
<Cheers
HEC is located in Pennsylvania....right in the heart of Amish country.? https://www.highenergycorp.com/
|
12 KW CCS ON 160-15M....USING THE 3CX-6000A7..... PART 17
12 KW CCS ON 160-15M....USING THE 3CX-6000A7..... PART 17
Here the grid and plate overcurrent protection, plus grid current and plate current metering are being done, using existing boards, with some component values modified for this application. The idea here is to be able to re-use the existing metering (100 ua meter movements), and re-scale them to what's required in the new amplifier. Existing metering (and mating overcurrent boards) was for another amplifier, which used lower value scales. Scott has several of these boards, all functional, so it was decided to re-use em for this application.
?
https://www.youtube.com/watch?v=0LaIcnQBuTo
|
Re: 12 KW CCS ON 160-15M...USING THE 3CX-6000A7... PART 15
Thanks Jim
I will avoid them. I used to buy a lot from Maxgain hopefully the AMp Repair guy will stock them and I will order some in the future,
Cheers
|
Re: 12 KW CCS ON 160-15M...USING THE 3CX-6000A7... PART 15
Those are the real deal? High energy corp? HT-57's.? ?HT-57's are not cheap.?
?
There is a chinese company on ebay, that sells their version of everything that HEC makes.....and also Draloric and other companies.? ?They have their own logo on them...and they look identical to the HEC / CRL versions.? The chinese versions are the same price as buying single lot qty's from HEC, so no savings there.? ?And the chinese versions don't offer qty bulk pricing, like HEC does.? ?Typ, the HEC version, from HEC is aprx $70.00? for 1-9 pieces, which drops a bunch with 10-24 pieces....then drops again with 25-49 pieces.??
|
Re: 12 KW CCS ON 160-15M...USING THE 3CX-6000A7... PART 15
Hi Jim
Are those HT57's the USA made ones or the Chinese ones. I notice that Ebay seems to flooded with fake HT57's or has High Energy moved their factory to China like everything else these days?
Cheers
|
Re: Amplifier failure to key
Thanks for the schematic. I'll keep it for future use just in case. Good job!
Gentlemen; Interesting and helpful dialog.? Thank you.? Steve, I didn't go down the path you describe too much because i had the plug and play cable.? I will look at that again to understand your testing process better.? I will keep it on file for next time.
But, the good news is the ARB-704 is back on line.? I traced the issue to a bad transistor.? Transistor Q1 (2n3904).? I was compounding my issue by having the wrong schematic.? The schematic that came in the 704 manual I received with the unit was not the schematic for my version.? Attached is the correct schematic.? I did call MFJ/Ameritron Group and talked with Rob.? He told me that often the large transistors with the heat sinks go bad (Q2 and Q3 (2n6740)).? They seemed to check out okay in my unit.
Once I replaced Q1 all was well.? I did not determine why Q1 failed but was pleased that after replacing it and powering things up it did not fail again.?
I believe that completes the loop on this repair.? I really appreciate the dialog and advice I received and hope my posting will be there for the next one faced with this or a similar 704 issue.? Thank you all for your interest and help.
73 Harrison N1FAM
|
Re: Amplifier failure to key
Gentlemen; Interesting and helpful dialog.? Thank you.? Steve, I didn't go down the path you describe too much because i had the plug and play cable.? I will look at that again to understand your testing process better.? I will keep it on file for next time.
But, the good news is the ARB-704 is back on line.? I traced the issue to a bad transistor.? Transistor Q1 (2n3904).? I was compounding my issue by having the wrong schematic.? The schematic that came in the 704 manual I received with the unit was not the schematic for my version.? Attached is the correct schematic.? I did call MFJ/Ameritron Group and talked with Rob.? He told me that often the large transistors with the heat sinks go bad (Q2 and Q3 (2n6740)).? They seemed to check out okay in my unit.
Once I replaced Q1 all was well.? I did not determine why Q1 failed but was pleased that after replacing it and powering things up it did not fail again.?
I believe that completes the loop on this repair.? I really appreciate the dialog and advice I received and hope my posting will be there for the next one faced with this or a similar 704 issue.? Thank you all for your interest and help.
73 Harrison N1FAM
|
Re: Amplifier failure to key
On my yaesu? FT-1000MP-MKV,? ( FT-1000D)? the tx inibit lead is always grounded...... until a mini-din plug is inserted into the yaesu mini din jack....at which point the grnd is removed inside the xcvr.?
|
Re: Amprepairguy Is Now The new Owner Of Harbach Electronics !!!!!!
Yup.? Everything will still be available. The Pentalabs 3-500Z's have already been added.? ?The 572B's are next.? ?Then the rest of the Pentalabs entire tube line up, including 8877, 3CX-800A7, GU-74B, FU-728F, 4CX-1000, 3x3/6/10/15/20 plus industrial / ism / broadcast tubes.? ? Jeff Weinberg is shipping a ton of stuff this Friday.? Dunno what the delay was, but it's finally sorted out.
|
Colin Kaminski
Bob