Compatible CRT for Tektronix 2225 - Page 1
Forum section: electronics / repair

author: giosif
author_rank: Frequent Contributor
timestamp: November 09, 2024, 04:27:27 pm
content: Hi,I have a Tektronix 2225 with a broken CRT and, apart from getting the exact replacement for it (already asked in the Buy/Sell/Wanted section), I was wondering what other scope model might be using a compatible tube.I have a 2235 scope and I was initially thinking of using the CRT in it, but then realized that tube has the connections to the deflection plates on its side, whereas the tube in the 2225 has all its connections on the neck connector at the back.Does anyone know of any other scope with a CRT like the one in the 2225?

author: bdunham7
author_rank: Super Contributor
timestamp: November 09, 2024, 05:08:59 pm
content: AFAIK, the CRT for the 2225 is unique to that scope and its relatively rare derivatives (see the Tekwiki page). The p/n is 154-0907-00 and I believe QService shows one available. IDK if a more common CRT might be made to work by rewiring the deflection grid circuits.Is your 2235 functional? If not, perhaps it would be better to repair that scope?

author: giosif
author_rank: Frequent Contributor
timestamp: November 09, 2024, 06:04:32 pm
content: Quote from: bdunham7 on November 09, 2024, 05:08:59 pmYeah, I was afraid that may be the case.Based on search results, it appears the Tektronix 2211 is another scope model using the same CRT.I did see the tube on QService's site, but the cost would be over EUR 130.Quote from: bdunham7 on November 09, 2024, 05:08:59 pmThis is what I am looking for.Quote from: bdunham7 on November 09, 2024, 05:08:59 pmIt isn't working, but I do not recall what specifically is wrong with it.Might be broken CRT as well.

author: Jeff eelcr
author_rank: Frequent Contributor
timestamp: November 10, 2024, 12:24:43 am
content: 2225 should be a common scope in europe, how much is a replacement or parts scope compared to the tube?Jeff

author: giosif
author_rank: Frequent Contributor
timestamp: November 10, 2024, 09:36:52 am
content: I couldn't find any for parts 2225 up for sale (or recently sold) on the bay, but working ones seem to go for over GBP 100.

author: factory
author_rank: Super Contributor
timestamp: November 10, 2024, 10:39:33 am
content: You need more patience, it can take a long time to find some parts, or a reasonably priced replacement scope of the same type. Too many lazy/stupid sellers using the flawed ePay AI pricing suggestions, why else would a 50MHz scope be advertised at such crazy prices?Quote from: bdunham7 on November 09, 2024, 05:08:59 pmIt isn't working, but I do not recall what specifically is wrong with it.Might be broken CRT as well.Why would the CRT be broken on 2 scopes? in my experience it's rare to find a broken CRT, lack of anything displayed is usually a fault somewhere else.David

author: George Edmonds
author_rank: Frequent Contributor
timestamp: November 10, 2024, 11:20:24 am
content: HiThe standard problem with ALL Tek 2000 series scopes is power supply electrolytics.I have several scrap Tek 2000 series scopes, but not a 2225. If you do try to replace te CRT with a different one please be aware that there are a number of PDA voltages used in the 2000 series.G Edmonds

author: giosif
author_rank: Frequent Contributor
timestamp: November 10, 2024, 11:54:05 am
content: Hi,I wish the problem with my 2225 was the electrolytics, but I'm 100% certain the CRT is toast (i.e. the glass pillars holding the electron gun and deflection plates have been broken on one of their ends and there are pieces of glass roaming freely inside the tube; otherwise, the tube still has vacuum).Converting another CRT for use in the 2225 is not something I'd engage in as a "quick project" and I was hoping to take advantage of any prior work done in this direction.

author: grumpydoc
author_rank: Super Contributor
timestamp: November 10, 2024, 01:19:23 pm
content: Quote from: giosif on November 09, 2024, 06:04:32 pmIf you are interested I have 2x 2235's, I don't have a 2225 (at least not that I spotted on a quick search - I'm sure Ihadone, but probably sold now).At least one of the 2235's should be working (or was when I put it away but that was quite a long time ago).If interested make me an offer, collection best & I'm in the Midlands. Will need at least one weekend to check that it works.

author: giosif
author_rank: Frequent Contributor
timestamp: November 10, 2024, 08:41:30 pm
content: Much appreciate the offer but, at this stage, my intention is to try restore the 2225.Thanks again!

author: grumpydoc
author_rank: Super Contributor
timestamp: November 10, 2024, 09:15:19 pm
content: Quote from: giosif on November 10, 2024, 08:41:30 pmNo worries, let me know if things change.In the meantimehttps://rsgb.org/main/news/rallies/

author: giosif
author_rank: Frequent Contributor
timestamp: November 11, 2024, 07:48:40 am
content: Will do.Thanks for the link!I was looking for such a list.