What spares to keep on hand for SE/30 repair?

[djc6]

What spares do you keep on hand for SE/30 repair? What are common failures? I’ve had the pleasure of recapping three so far and have had to replace the following ICs, all in video circuit:

• LS393 - I have replaced two of them (one UG8, one UF8 on two separate boards).
• LS166 - I have replaced one
• 253 muxes - have spares, haven’t had to replace any

Any other common failures? I am putting together a mouser order and just wondering what else might be handy to keep on hand.

 

[smrieck511]

I kept picking up SE's when they were cheap for all the parts except the SE/30 logic board. And I restored a second SE/30 as well. I have extra RAM, ROM, Video ROM and whatever the graphics chips are for UE8 etc. (my best repair day was when I brought the second SE/30 back to life by replacing UE8 and of course the caps - never heat-gunned a chip off before) So I have the SE/30 I use plus a second restored SE/30 and three SE's in my closet. Overkill. I guess the flyback transformers and crt's eventually go so it's nice to have several more of those.

 

[s_pupp]

I have CRT’s, NOS flybacks, a couple bad logic boards for parts that can’t be obtained elsewhere, and the following recently purchased IC’s that are corroded by capacitor electrolyte on (all of) my boards:

1. AMD AM26LS30JC (had to buy in a pack of 46)
2. SN74LS166AD (Digikey part# 296-33968-5-ND)
3. SN74F253DR (Digikey part# 296-31764-2-ND)
4. SN74LS393DR (Digikey part# 296-29007-2-ND)
5. SN75175D (Digikey part# 296-6856-5-ND)
6. TL071BCDR (Digikey part# TL071BCDRTR-ND)

Some of these parts are listed as obsolete by Digikey, and won’t be repleted once the current supply is exhausted.

If I purchased the wrong parts, I hope to be corrected.

 

[Callan]

I'd add some crystals to the order (all 3). Ive had quite a few bad. I'd also get some video rom and pal sockets..

 

[s_pupp]

I'd add some crystals to the order (all 3). Ive had quite a few bad. I'd also get some video rom and pal sockets..

Do you know if the two small radial crystals are the same as each other, and what the specs are? I believe them both to be 32.768kHz, but am uncertain, and don’t know their capacitance or ESR. Are crystal capacitance and ESR critical for the SE/30, or can any of the several available radial can crystals of the required frequency be used?

 

[djc6]

Do you know if the two small radial crystals are the same as each other, and what the specs are?

I remember a group buy for SE/30 reloaded boards had a nice BOM attached. Here is the thread: https://tinkerdifferent.com/threads/so-you-wanna-start-an-se-30-reloaded-group-buy.2936/

Here is the BOM: https://docs.google.com/spreadsheet...bEiThW19gc/edit?gid=1837251752#gid=1837251752

The third tab of the BOM spreadsheet "Top-Side Special Parts" shows different parts for Y1 and Y3. To me that is a strong indication they are different on the original board as well, but I'm not familiar enough with SE/30 to say for certain.

 

[s_pupp]

I remember a group buy for SE/30 reloaded boards had a nice BOM attached. Here is the thread: https://tinkerdifferent.com/threads/so-you-wanna-start-an-se-30-reloaded-group-buy.2936/

Here is the BOM: https://docs.google.com/spreadsheet...bEiThW19gc/edit?gid=1837251752#gid=1837251752

The third tab of the BOM spreadsheet "Top-Side Special Parts" shows different parts for Y1 and Y3. To me that is a strong indication they are different on the original board as well, but I'm not familiar enough with SE/30 to say for certain.

Great resource, and one that answers a few more questions I had. Many thanks, indeed!

 

[djc6]

6. TL071BCDR (Digikey part# TL071BCDRTR-ND)

I am curious why TL071B vs TL071 ?

looking at the datasheet they have different electrical characteristics, but I'm way over my head.

http://ti.com/lit/ds/symlink/tl071.pdf?ts=1746899259882&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FTL071

 

[s_pupp]

I am curious why TL071B vs TL071 ?

looking at the datasheet they have different electrical characteristics, but I'm way over my head.

http://ti.com/lit/ds/symlink/tl071.pdf?ts=1746899259882&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FTL071

The op amp on my logic board is a TL071B, and I wanted to stick with a direct replacement. Looking over the datasheet, page 17 lists the B version as having a lower input offset voltage, so it seems to be a somewhat higher spec device. I don't imagine this makes much of a difference in this case, given that its function is as an audio amplifier; being a hobbyist with no formal training, however, I would rather not make assumptions.

 

[djc6]

The op amp on my logic board is a TL071B, and I wanted to stick with a direct replacement.

You are right, pulling out two of my boards they both have a TL071B as well. I was curious because two different BOMs for SE reloaded board show regular TL071. Thanks for the info!