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Quality of 833C tubes on eBay

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Kiwihvguy

Sun Aug 21 2016, 11:18PM

Registered Member #3395 Joined: Thu Nov 04 2010, 08:42AM
Location: Christchurch, New Zealand
Posts: 193

Hi all,

Have been doing some research on places to buy some 833C tubes for a future VTTC project.
I have uncertainty about the quality of this particular deal on eBay, mainly because there is no visible brand name on the glass envelope of the tube: http://www.ebay.com/itm/833C-A-vacuum-tubes-2-pcs-warranty-best-quality-available-/231230691774?hash=item35d66c59be:m:mft2zP35JRkxddzrbhZCDqw

I'm located in New Zealand, so the long haul for the package to travel from the States to here is obviously a concern because it will be a fragile package. I would feel more secure in buying from a branded 833C from RF parts or Pentalabs, as I have found from other forums on 4hv.

Is there anyone with previous experience who could advise whether it's more advisable to purchase from RF parts/Pentalabs or is this deal on eBay not dodgy? Obviously keep in mind I'm more concerned about buying a genuine tube that will be shipped safely too.

NgÄ mihi,

teravolt

Mon Aug 22 2016, 10:53PM

Registered Member #195 Joined: Fri Feb 17 2006, 08:27PM
Location: Berkeley, ca.
Posts: 1111

I bought from rf parts and they have a couple version of this tube the A and C the last one was 150 after S+H was added but it was guaranteed jus inspect the insides and the envelope and take pictures with date incase you have to return. Ebay you may or may not be able to return just make shure the envelope is clear and the pictures that they present are clear so the guts are visible.

Mads Barnkob

Tue Aug 23 2016, 07:38PM

Registered Member #1403 Joined: Tue Mar 18 2008, 06:05PM
Location: Denmark, Odense C
Posts: 1968

From what I read on diyaudio.org, Pentalabs are "branded" but Chinese tubes just like the "833C" big white letter ones.

The Pentalabs are properly tested and could be considered 1st sorting quality and the "833C" could be those failing such quality demand. Just speculations.

Kiwihvguy

Wed Aug 24 2016, 06:20AM

Registered Member #3395 Joined: Thu Nov 04 2010, 08:42AM
Location: Christchurch, New Zealand
Posts: 193

Good to know, thanks for the advice.
Any others wishing to comment?

nzoomed

Sun Aug 28 2016, 09:06PM

Registered Member #54503 Joined: Sun Feb 22 2015, 10:35PM
Location: New Zealand
Posts: 288

Firstly, great to see another member here from New Zealand!

Have you tried Geoff Edwards from Valve Radio Spares in Christchurch?
He may or may not have them, but he stocks all kinds of tubes so if he has some, they are a good chance to be good quality NOS tubes.
His email is:
**link**

Tell him Shaun referred you ;)

Kiwihvguy

Wed Aug 31 2016, 03:50AM

Registered Member #3395 Joined: Thu Nov 04 2010, 08:42AM
Location: Christchurch, New Zealand
Posts: 193

nzoomed wrote ...

Firstly, great to see another member here from New Zealand!

Have you tried Geoff Edwards from Valve Radio Spares in Christchurch?
He may or may not have them, but he stocks all kinds of tubes so if he has some, they are a good chance to be good quality NOS tubes.
His email is:
**link**

Tell him Shaun referred you ;)

Hi Shaun,
Also great to hear another person from NZ! Yes interestingly enough another person from an amateur radio club in Christchurch also referred me to Geoff while I was asking around for some tubes.

Just gave Geoff a call yesterday, he's going to have a hunt around for some 833s.

nzoomed

Wed Aug 31 2016, 12:11PM

Registered Member #54503 Joined: Sun Feb 22 2015, 10:35PM
Location: New Zealand
Posts: 288

Kiwihvguy wrote ...

That's great, he should be able to help :)

Kiwihvguy

Thu Sept 01 2016, 11:52PM

Registered Member #3395 Joined: Thu Nov 04 2010, 08:42AM
Location: Christchurch, New Zealand
Posts: 193

Also, out of curiousity, what other vacuum tube models will also be suitable in place of an 833?
Given the voltage rating is 4kV and 1.8kW (forced air cooling).

Would be helpful to get an idea of all the other options for tubes to use :)

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