Ok Nixie fans riddle me this. BOM says 10k 1/3W Diagram says 18k and these toasted ones read 39k ![WTF? :wtf:](https://www.eevblog.com/forum/Smileys/default/wtf2.gif.pagespeed.ce.pxLiY5pjs4.gif)
They are the current limiting resistors btw.
Carbon compisition resisitors, which I presume those are, have two relevant characteristics compared with metal film resistors. CC resistors tend to drift high, and they are relatively tolerant of surges.
Well these ones clearly have failed and those types are always high on my list of suspects when things go wrong and replacing these with their equivalent ones in square edge or metal film types is preferable, as recommended by Mr Carlson,
Carbon composition resistors should be reserved for selling to audiofools ![Smiley :)](https://www.eevblog.com/forum/Smileys/default/xsmiley.gif.pagespeed.ic.R8GFI-pF6f.png)
Things that bugger up carbon composition resistors: vibration, applying voltage, heat, moisture, age, moon phase, looking at the stripes too long.
Surges; that's what those nice hybrid resistors are for these days.
Quite correct. ![Laughing :-DD](https://www.eevblog.com/forum/Smileys/default/smiley_laughing.gif.pagespeed.ce._hfWAz_QHO.gif)
Are they just the bias ballast resistors, or are they actually in the signal path? If not, then no reason not to replace with metal film resistors. Even if they are in the signal path it probably won't matter, as old & slow as that thing is.
I remember back when I was very young... I used to scavenge all the glass-substrate film resistors out of old color TVs, then soak and scrape the coating and caps off. The resulting semiconductor-coated glass cylinders (they typically ranged from 3mm x 10mm to 8mm x 100mm or so) simply fascinated me; there were so many variations in the translucent color, and the cut pattern was so "Sci-Fi Story Doomsday Device" looking.
I used to collect them in groups and make enclosures with lights behind them, then imagine them as the energy source in my very own "personal LASER"; built from scratch to do... well, whatever I damn well wanted to do, it was a fekking LASER, man!
![Laughing :-DD](https://www.eevblog.com/forum/Smileys/default/smiley_laughing.gif.pagespeed.ce._hfWAz_QHO.gif)
And then, after Star Wars, and the oodles of books... I of course imagined them as Khyber crystals and fabri-cobbled, then as a teen in school I actually machined, my own LASER swords (yes, I know they're commonly called "light sabers") around them decades before places like Master Replica and Ultra ever imagined making them.
I never dreamed I'd one day be able to buy such a thing as a hearing-aid-battery-powered LASER pointer for four bits, or a real VISIBLE LIGHT (ZOMG!!!) green or blue LASER pencil capable of emitting actual destructive energy for the price of a sandwich & chips... and that they'd all be solid-state devices. Honestly, it STILL boggles my mind.
![Shocked :o](https://www.eevblog.com/forum/Smileys/default/xshocked.gif.pagespeed.ic.CrwtrNUjLO.png)
Nice. I could do with a set like that. Very expensive though. £300+ for a proper development kit. Bought a whole book of cheap Royal Ohm resistors for development. Unfortunately I run a "swept bench" i.e. throw components at a design and then sweep them into a bag when done. So I'm already running out of loads of values. ![Sad :(](https://www.eevblog.com/forum/Smileys/default/xsad.gif.pagespeed.ic.L3FGyzQrjB.png)
Decided next time to just buy Vishay MRS25's on demand and spreadsheet it properly. And you know what, check the sodding back order lead on the things
https://uk.rs-online.com/web/p/through-hole-fixed-resistors/6833165/
There are a number of vendors on AliEx selling assortments of cut-reel reclaimed passives of all sorts; I've even bought 1/2 watt axials in corrugated cardboard magazine format from there that have to be 40 years old.
I run a swept bench too... I sweep them all into a plastic shoebox.
I have one for resistors, one for caps, one for semis and one for "Damifino". These are what I dig around in first when I'm just noodling around on hobby projects or, when I need some time doing a repetitive activity for "mental floss", I'll sort them into little pill boxes. :p
mnem
https://youtu.be/vOjPBBvBe2c