eHam.net - Amateur Radio (Ham Radio) Community

Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net


Reviews Categories | Electron Tubes | Cetron Jan 811A Help


Reviews Summary for Cetron Jan 811A
Reviews: 10 Average rating: 3.0/5 MSRP: $$25
Description: Would like to give positive review of Cetron Jan 811A.
Product is in production.
More info: http://
Email Subscription
You are not subscribed to this review.

Subscribe!
My Subscriptions
Subscriptions Help

You can write your own review of the Cetron Jan 811A.

K2LRC Rating: 1/5 Jan 3, 2015 12:15 Send this review to a friend
Do not buy these - Surplus Sales  Time owned: 3 to 6 months
Well my story is a bit long in that I have bought 6 or 7 sets of matched 811A Cetron tubes from Surplus Sales of Nebraska. I had failures at turn on on two sets. Surplus Sales was willing to replace one of them and after pushing them they agreed to replace the second one. I tried to buy more of these and Surpus Sales refused to sell me any more since I had failures that they have blamed on me. I repair many of the Colins 30L-1's and I know what I am doing. They just did not want to do business with me again due to there crappy tubes.
STAY AWAY FROM THESE GUYS !!!
 
KF7VXA Rating: 3/5 Dec 17, 2014 19:16 Send this review to a friend
Great Tubes..But...  Time owned: 6 to 12 months
The tubes worked great for about 6 months. One tube lost it's seal at the base, blowing a Cap in my AL-811. An easy fix, but when I went to remove the other two tubes for the repair, the cement on the top caps came loose from the other two, even though I was careful as could be. One ruined the envelope, the other just came loose.
Great performance, but the sealing cement does not hold up with age.
I won't buy another set; the extra cost was not worth the extra performance.
If you buy a set, be very careful putting on the connection to the cap, and if you plan on removing the cap connector, be ready to ruin the tube.
 
AA2SM Rating: 0/5 Dec 27, 2010 09:21 Send this review to a friend
A Waste  Time owned: 0 to 3 months
My Ameritron 811 Amp is three years old an really enjoyed it. My original taylor tubes lasted over a year and kept one good tube from the original aside. Replaced with another set of Taylors. Ran great until about 2 weeks ago. Saw that one tube was dark so decided to order the Cetrons 811. Wow my amp went bizerk. Could not tune it up. SWRs all over the place. Finally I got 350 watts out and that didn't last long. Amplifier got real hot. I admit Ilm not the smartest fish in the ocean but when I combined the one good taylor tube from my original set with the two from my second , my amp ran great. 600 watts out easy and ran cool. Im packing my cetrons up for the garbage.
 
XMWUF Rating: 4/5 Nov 28, 2010 01:30 Send this review to a friend
Great buy!  Time owned: 0 to 3 months
These tubes came with 1988 date code. Worked very well so far. Caps were intact on delivery. Power out measured easily as well as the 5 year old Ameritron tubes that came with the 811H. Thanks Nebraska Surplus!!
 
W6WUH Rating: 4/5 May 27, 2010 18:11 Send this review to a friend
Gm 900 RCA Gm1300 +  Time owned: more than 12 months
I don't think there is any question that the american made Cetrons are superior to any of the chinese made tubes.

However, I did measure the transconductance of a pair of NIB Cetron Jan 811-A tubes and found them to both measure 900. New RCA Jan's will measure about 1350.

In linear amplifier service this probably won't matter. Most vacuum tubes that test 80% of new work exactly like new ones, so long as they have 100% filament emission !

What will matter is the quality of the filament contruction... the getter, and coating on the plate. Thorium and the other rare earth metals and the vacuum equipment and HV testing are also critical.


The American tubes are surely going to excell in this department ! No cigarette butts found in a Cetron that I have heard about !

Why not use some permanent high temp locktite,
or even super glue on your plate caps before you install them ? Glass to metal contact area.

It isn't hard to re-solder plate caps, if you don't break the envelope !

Surplus sales claims to have several thousand of 811-As.. with discount for qty. Get some.
 
K1DT Rating: 4/5 Oct 8, 2008 09:14 Send this review to a friend
Fine Tube - But Handle w/Care!  Time owned: 0 to 3 months
Nice tubes at a nice price from the nice people in Nebraska. These are USA made, NOS 1988 date code, RCA/JAN type construction. They work very well. BUT - be Very Careful with the Plate Cap! The plate cap cement has dried out and failed, likely NG right from the factory. Even knowing this problem (there is also a warning on the invoice) and using utmost care, I cracked the seal on one by simply pushing on the plate connector, the only tube I have ever broken in 40 years. My advice: for this good price buy an extra tube and be EXTRA Careful. Some add a bead of JB Weld epoxy (500 deg F rating) around the plate cap but I have not tried that. And don't spend any extra for "Matched Sets", in my opinion this is total nonsense unless you are using the tubes in a fixed bias push-pull audio amp. 73, Tess - K1DT
 
K3VYY Rating: 5/5 Jan 31, 2008 11:38 Send this review to a friend
Great!  Time owned: 0 to 3 months
I recently found the Chinese "P" 811's in my had a couple with the bulb separated from the base. I purchased a matched quad of the Cetron 811A's from Surplus Sales of Nebraska, and WHAT A DIFFERENCE. More power output, and they seem to load better. Very Happy.
 
K8DXX Rating: 0/5 Feb 3, 2001 19:13 Send this review to a friend
OLD JUNK  Time owned: more than 12 months
In my previous review, I reported having problems with the glue and seals on JAN Cetron 811As purchased for my Ameritron amp. First set was useless but the second set seemed OK. Well... yesterday I opened up my AL 811H to replace those Cetrons with Taylor 572Bs (no more power expected, just greater durability). Anyway, the anode caps on 2 of the 4 were already detached and hanging over to one side. Of the four tubes, I could remove only 1 without them loosing their caps and seals.

I talked to some guys on 3865 and 3875 last night. Several reported having similar problems, probably because these tubes sold by Surplus Sales of Nebraska are just that, "surplus," from which war I don't know. We suspect that the glue dries out with age.

I also emailed Surplus Sales... and asked for an "adjustment" or a partial credit toward purchase of more 572Bs. My request was refused; "no adjustment is possible." I do understand that the tubes were almost 2 years old. Funny thing though, my otiginal set of Chinese 811As are fully intact and easily endure the rigors of an install/deinstall. They also still produce nearly full output.
 
K8DXX Rating: 4/5 Jan 26, 2001 00:31 Send this review to a friend
First set defective  Time owned: more than 12 months
My AL811H came with Pride (Chinese) tubes. They worked fine but always made a strange noise when lit. So, after three years, I purchased a matched quad from Surplus Sales of Nebraska. 3 of the 4 tubes had faulty seals or glue jobs on the anode cap because they broke off during installation. The vendor quickly replaced them. Since then, they have worked fine.
 
JAMES_BENEDICT_EX_N8FVJ Rating: 5/5 Dec 22, 2000 21:22 Send this review to a friend
Excellent Product  Time owned: 0 to 3 months
Tested four new Cetron Jan 811A tubes in an Ameritron AL811H amplifier. These tubes were compared to a new set of now discontinued Svetlana 811A tubes. The Cetron 811As produced about 25 watts higher output over the excellent Svetlana tubes. Tuning the AL811H was exactly the same and the input SWR did not change. The Cetron has the 'U' shaped ribs on both sides of the plate just like the older RCA 811A. Highly recommended!
 


If you have any questions, problems, or suggestions about Reviews, please email your Reviews Manager.