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| Reviews Summary for CHINESE 572B TUBES |
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Reviews: 10
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Average rating: 4.1/5
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MSRP: $varies in price.
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Description: High-mu power triode for use in Class AB2, Class B, Class C RF, and audio amplifiers. The chinese 572B is virtually an exact copy of the original 572B/T160L tube and normally rebranded.
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Product is in production.
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More info: http://www.tomstubes.com/572b.htm
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write your own review of the CHINESE 572B TUBES.
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VK4VDX
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Rating: 5/5
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Sep 14, 2011 21:29
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beyond your control
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Time owned: more than 12 months
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Shipping damage is the only problem you will have with this Tube, they are always boxed well and still there is a big chance of them arriving damaged. Having lived in China and experienced EMS (freight company) first hand.
If you want to send a parcel, EMS is great, they will pick up your parcel with a bicycle from your home or office and take it to the next depot, surprising how much they can fit on that bike and than you got customs if they check the parcels on the way out of the country not knowing what is really in the parcel. the same can happen on the way into your country. So my suggestion is, if you need 2 tubes, buy 4, because if 1 tube breaks you will be asked to send that tube back to china, that's if they offer to replace the tube but most of the time you will get told if the tubes get damaged during shipping the tubes will not get replaced free of charge.
That's why my Tubes have come in my mother in laws hand luggage the last time she arrived from China for a visit.
I have had some excellent reports of a technician who has really put the tubes to the test and he told me on more than one occasion how surprised he is about the quality of these tubes. That's why I will give these tubes a "5"
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SV9OFO
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Rating: 5/5
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Dec 29, 2010 00:08
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I ACTUALLY BOUGHT THEM FOR BREAKING THEM!!!
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Time owned: 0 to 3 months
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No problems at all. Have bought them after installing major PSU safety upgrades (all amps should carry those, as a 300 mA per tube fuse at HV and a 22 ohm R in series) and during the refurbishment of my FL-2100Z, for not breaking my pair of new Cetron's.
Drop-in replacements for Cetron, they had undergone enormous stress during the testing phase. Key down 600W carrier for minutes boiling my dummy load's oil - no failure. Some graphite glow but no harm.
My chinese friends busted through a TI pileup yesterday morning (I reside in southern Europe).
Did that AFTER the punishment.
My Cetrons are still in the box, and probably will remain there for long as I see it.
Will definately buy again.
73
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N1CKX
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Rating: 5/5
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Sep 28, 2010 17:56
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Working Fine
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Time owned: 0 to 3 months
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Ordered 4 Shuguang 572b tubes from E-bay/China to back up the tubes in my MFJ/Ameritron AL-572 amp, as I had a bad one in the Amp from the factory (another story).
Arrived in a week, well packaged. Gave them a careful inspection under high magnification for bent/distorted elements, and then checked them for shorts.
Installed them in the amp and have been running them for over a month with no issues.
Carefully measured the output with a calibrated dummy load and a 200mHz scope and output is around 1380 watts PEP. Pretty darn close to legal limit. Not bad for less than $150.00 for four tubes.
My original tubes are (a month later) still at MFJ/Ameritron. Way to go MFJ/Ameritron.
I would have an $1800.00 paperweight if I had not purchased backups.
I suspect the tubes that short are going into old Heathkit Amps that mount the tubes horizontally.
These tubes are rated for vertical mounting. Elements can sag when horizontal and short out.
The original tubes in those amps were special construction for Horizontal mounting.
I’m holding my breath, but will give them a 5/5 for now.
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PA1ZP
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Rating: 4/5
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Aug 11, 2010 00:28
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Service OK
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Time owned: months
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Hi All
I bought 18 572 tubes at factory in China.
Delivery was perfect packaging perfect, price perfect.
Only one tube was not 100%, it rattled loose anode in glass envelope.
17 tubes were OK.
In use now fer 6 month, no problem at all.
You can complain abt the one defective tube , but with my Ameritron on delivery came a tube with the same defect.
It was only after arrival of 18 the chinese tubes that I found out what was the problem with the original set of tubes.
One was defective from day one (not causing serious touble but just strange noises from vibrating anode against glass envelope)
Noises are gone with new set of tubes installed
Original Chinese set of Ameritron was in service for 3 yrs and completely warn.
(they had a hard life with 1KW key down in CW and I tend to TX for more then 20 minutes at a time without pause), they had to work full pull 70% of my QSO's, 100 watt in and 1KW(+) out fer 1 hour or more every day.
I couldn't get over 800 watts key down anymore and SWR at input was becoming higher.
Anode current would not pass 575 mA no more, even with 100W input.
But after 3 yrs Anode top resistor and coils 100% and grid resitors 100% like new.
New set was Ok from day one.
No more strange noises.
I know that the 572B and the AL572B amp are not the best in town but 4 tubes cost me 120 Euro's now, if they last another 3 yrs I am quite happy.
You have to be realistic AMP is cheap tubes are cheap don't compare the 572B with a 3CX1500 or 8877m, though our chinese friends at High Hope International deliver up to 3CX50000.
3-500 3cx1500 3cx800 etc. all produced by them in China.
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VE3FDT
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Rating: 1/5
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Oct 31, 2009 19:33
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QC sucks!
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Time owned: months
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I have bought a matched quad (4 tubes) from an eBay seller in Hong Kong. The price was more than reasonable, the delivery cost and time was good. The quality sucked big time.
Out of 4 tubes all had very nice gold metallic stickers on them saying "QC Passed", beyond that one had a direct grid short causing my amplifier to blow a fuse on applying HV (this required replacing blown grid resistors) and another tube had a loose pin (while this is not an outright failure it causes a plate current spike on applying HV / closing the relay and makes me wonder how much longer this tube is going to survive).
The Chinese vendor agreed to replace the shorted tube, but the one with loose pin is apparently OK for him / her. Only that it has been almost a month now and the replacement tube has not been shipped yet. The concept of QC and standing behind the product you sell seems to be entirely foreign to those guys.
In my personal experience the Chinese 572Bs are about 60% of the price of the other such tubes readily available, the problem is that their failure rate is 50% which makes them more expensive in real terms than other 572Bs offered for sale nowadays. Nobody behind the product either.
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W7EKB
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Rating: 4/5
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Jul 9, 2009 22:05
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OK Tubes
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Time owned: 0 to 3 months
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I bought a pair of Shuguang 572B tubes for my SB-200 from a seller on Ebay at least a year ago, and put them away as spares, since I had several good used Cetrons.
In the last several months the power output has been dropping until maximum power output was only about 350 watts.
So I tested all the remaining tubes I had, including at least 6 Cetrons, 1 Penta Labs, and the 2 new Shuguang tubes.
4 of the Cetrons were practically useless, and the Shuguang tubes showed the best output (naturally). I installed the fairly decent pair of Cetrons, and within only a few minutes, there was a flash in one of them, and the filament got considerably dimmer. Power output dropped by at least 100 watts.
So, I uninstalled those, and installed my "new" Shuguang tubes.
Within an hour after installing them, one of THOSE flashed and exhibited a solid grid-to-filament short.
Examining the tube closely, it looked as though the filament "press" was slightly off-center, putting the filament closer to the grid on one side than on the other.
I had recently bought another SB-200 which had a pair of Shuguangs in it. This particular amp had been abused by a CBer, as the plate coil had been charred nearest the tube on that side, the 10 meter tap had been moved so it would "work better" on 11 meters, the plate tuning capacitor had been "arced" badly, and the 10 meter grid coil had been rewound.
Nonetheless, when I substituted one of the Shuguang tubes out of the CB-ed amp for the shorted one, the SB-200 showed full power output, over 700 watts on 80 meters, and has been working fine ever since.
The way I see it, since an NOS 572B from AES costs $152.00 EACH, I can buy 4 of the Chinese tubes for that amount and lose two and still make out.
However, I DO wish QC in the Chinese tubes was better...
There is a fellow on eBay who sells Svetlana 572Bs for a fair price. He says that the Chinese tubes have a 35% failure rate.
So far, since I have 4, and one has failed, I have experienced a 25% failure rate.
Now, I will see how long these good ones last, and will report back in a few months.
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KX5JT
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Rating: 5/5
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Mar 31, 2009 05:49
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Strange!
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Time owned: 0 to 3 months
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So I put that matched pair back into the SB-200 after a while and the plates DO NOT turn very red at all now. I have NO IDEA what happened. Same settings on the amp, same loading.... maybe the getters weren't complete and the red plates finished them? At anyrate, they are working FB now! Mysterious but I'm happy!
KX5JT
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KX5JT
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Rating: 2/5
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Mar 11, 2009 01:34
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Stay away from Shuguang 572Bs!!!
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Time owned: 0 to 3 months
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Hello everyone. This is a warning to stay away from Shuguang 572B tubes as direct replacements for amps designed for 572B's. I own a Heathkit SB-200 and decided to try a matched pair. After ordering direct from Hong Kong from that JCCsomething fella on Ebay, they arrived at my home well packed and timely. No problems there. The problem is when you put 2400 volts of plate voltage on them as the original 572Bs are specified for and as many of the amps that use 572Bs utilize. The plates will glow a BRIGHT CHERRY RED in less than a minute of talking with ssb. RTTY will have them glowing RED HOT in less than half a minute. Graphite anodes should just barely blush a deep red not a bright red hot cherry red. I found out the reason too. See here....
http://www.analogmetric.com/forum/viewthread.php?tid=223
Check the specs on those Shuguang 572Bs... they are only rated for 1250volts on the plates. THAT IS less than HALF of the voltage rating of original 572Bs... .unless you are designing your own amplifier/transmitter with this low plate voltage, this is useless for replacing 572Bs. Real 572B's should be able to take 2750 volts on the plate in intermittent amateur service. My Sylvania Made in the USA 572B's barely blush when I run AM continuous carrier or heavy duty RTTY or SSTV. You have been forwarned! Svetlana 572B's from the 1990s maybe a better choice. I understand the newer Svetlana 572B's were designed with audio in mind and they may not be a good choice. Anyway, I am in the process of putting a matched pair of NOS Svetlana 572B's through a burn in and will report on my findings with them in the near future. *Sigh*
Caveat Emptor
John KX5JT
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N3OQD
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Rating: 5/5
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May 12, 2008 20:52
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brief overview
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Time owned: 6 to 12 months
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I put a set in my Ameritron AL-811. In this application they serve me quite well. With the larger graphite anode of the 572B in the stead of the 811a's tin steel type, these are more forgiving and more durable. Even Ameritron recommends this upgrade with no hesitation. 40w drive gives me about 400w out SSB consistantly. Have a set in the wings but I may never need them. $75 plus shipping for the three from China on e-bay
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K4SPS
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Rating: 5/5
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Jun 27, 2007 21:05
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Have had great luck with these. Thank God for the Chinese, Ha!
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Time owned: 0 to 3 months
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I ordered, directly from China, a matched set of four 572B's for my 'new' Collins 30L amplifier. They arrived in perfect shape and tuned up with no problems. They run cool and efficiently in this classic amp. Will probably buy a spare set to have a lifetime supply of valves. I highly recommend them; hopefully, you will have similarly good luck! K4SPS
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