Apple IIe card - oscillator damage

[wottle]

I helped a guy in my area by recapping his LC logic board and its power supply. Well, he found his Apple IIe card for it and unfortunately it looks to be in very bad shape.

Looks like that capacitor on the left has eaten away what look to be two oscillators? Just with different frequencies? Maybe it’s just surface rust and corrosion, but I was trying to look for the parts and couldn’t find anything when I searched for them.
Anyone know if there are modern replacements for these?

Also, how reparable is this card? I can generally repair damaged traces if I can see them and track them, but I’m assuming this board doesn’t have schematics. Is it a two layer board that I might be able to fix any traces I find damaged, or is it going to be a multi layer board where I am out of luck without schematics or another board and countless hours of probing pins?

hanks for any guidance you can provide?

 

[JDW]

Note sure how "repairable" the IIe Card is, but mine had leaky caps and I cleaned and swapped them out and had no issues, but mine wasn't damaged like yours. No broken traces or eaten through feet on mine at all.

Screen capture from my IIe Card video shows the larger XTAL (full-sized can) to be SARONIX 9214P, 17.2340MHz, 197-0566E. The smaller Y1 XTAL is marked S0100 (14.318MHz).

Not wanting to spend an hour digging deeper, I asked ChatGPT to dig up the original part data sheets to find the specs and see what modern parts are available. It came back with the following:

Prior to tariff madness in the USA, your best bet for getting a custom XTAL was AliExpress. Technically, it still is, although I have no idea what the taxes would amount to. Then again, these people will likely price it at $0.50 so it won't matter. In the past, I have used these guys with success in getting custom speeds made without any bulk order commitment, but I don't know if they will do 17.2340000MHz, so you will need to ask them. Ask And Ye Shall Receive is the name of the game, so don't be afraid to ask:

TCXO Full-Size 25M 25MHZ 25.000MHZ Rectangular Temperature Compensated Crystal Oscillator DIP-14 High Precision 3.3V-5V ±0.1PPM - AliExpress 502

Smarter Shopping, Better Living! Aliexpress.com

www.aliexpress.com

You technically don't need the stability of a TCXO, so be sure to ask if they offer 17.234MHz in a regular XTAL or TXCO.
WARNING! Make ABSOLUTELY SURE you ask for 5.0V XTALs or they will send you 3.3V instead!!

DigiKey link to Replacement suggested: https://www.digikey.com/en/products/detail/ilsi/hc49us-ff3f18-14-31818mhz/12610247

 

[wottle]

That's awesome information. Your link didn't work in the US, but I found this seller who was willing to make one in that frequency with 5v in the DIP-14 full size. https://www.aliexpress.us/item/3256808009232675.html?gatewayAdapt=glo2usa

I'm just waiting on confirmation from the guy that He'd want me to try to get it working. Looks like it could be a challenging project, but would be really cool to resurrect it.

Thanks as always for your help!

 

[JDW]

If you have experience buying on AliExpress, then you need no advice from me. But if you don't have much experience, then I will merely suggest that you seek out the most reputable seller you can find. (Even then, it's somewhat hit or miss.) I tend to look for items on want to buy there and see if at least 10 people are listed as having made a purchase from a given seller. The more people I see having purchased a given item, the more secure I feel about buying from the seller. Conversely, if there's not a single purchase, I then must consider if it's a specialty item that most people wouldn't necessarily buy, and I guess a XTAL qualifies as that. Then you just need to make sure you have good communication with the seller, and verify that shipping costs aren't too outrageous.

For folks living in the USA now, the next step would be to ponder what your order total will come to, and then specifically ask them how they will declare the value. Some people will start getting preachy about "ethics" at this point, and that's perfectly fine. I am not advising anyone to lower their moral standard or do the wrong thing. But you basically need to assess about how much you will be charged to bring stuff from China into the USA. I know we all want to scream: "It's only a freakin' XTAL, for goodness sake!" And that is true! You just want to be sure the total cost for that little XTAL isn't more than you're willing to pay.

Please let us know how it works out in the end in terms of your IIe Card repair!

 

[Nycturne]

I'm just waiting on confirmation from the guy that He'd want me to try to get it working. Looks like it could be a challenging project, but would be really cool to resurrect it.

Considering how rare these are starting to get, I hope he says yes. Fingers crossed that the capacitor hasn't eaten too many traces. It looks to be in pretty good shape otherwise.

This reminds me I need to make sure I have the right parts on hand to recap my own IIe card here soon.

 

[wottle]

Considering how rare these are starting to get, I hope he says yes. Fingers crossed that the capacitor hasn't eaten too many traces. It looks to be in pretty good shape otherwise.

This reminds me I need to make sure I have the right parts on hand to recap my own IIe card here soon.

Yeah, the card is on its way to me. I got caps and the Y1 on the way from DigiKey. I was able to find what appeared to be a reputable seller who responded when I asked about custom frequency. He even followed up to confirm 5V, which I appreciated.
After I get the card and remove the caps, I’ll be neutralizing any electrolytic juices in the board with some vinegar, cleaning in IPA, and inspecting under the caps and the oscillators. I’m hoping there aren’t too many traces under there, but we’ll see.

A good reminder to recap any expansion cards you may have in your machines.

 

[wottle]

If you have experience buying on AliExpress, then you need no advice from me. But if you don't have much experience, then I will merely suggest that you seek out the most reputable seller you can find. (Even then, it's somewhat hit or miss.) I tend to look for items on want to buy there and see if at least 10 people are listed as having made a purchase from a given seller. The more people I see having purchased a given item, the more secure I feel about buying from the seller. Conversely, if there's not a single purchase, I then must consider if it's a specialty item that most people wouldn't necessarily buy, and I guess a XTAL qualifies as that. Then you just need to make sure you have good communication with the seller, and verify that shipping costs aren't too outrageous.

For folks living in the USA now, the next step would be to ponder what your order total will come to, and then specifically ask them how they will declare the value. Some people will start getting preachy about "ethics" at this point, and that's perfectly fine. I am not advising anyone to lower their moral standard or do the wrong thing. But you basically need to assess about how much you will be charged to bring stuff from China into the USA. I know we all want to scream: "It's only a freakin' XTAL, for goodness sake!" And that is true! You just want to be sure the total cost for that little XTAL isn't more than you're willing to pay.

Please let us know how it works out in the end in terms of your IIe Card repair!

I forgot to ask. Is there an easy way for me to test this when it arrives before installing? Can I send 5v through it and see the frequency on an oscilloscope?

 

[JDW]

I forgot to ask. Is there an easy way for me to test this when it arrives before installing? Can I send 5v through it and see the frequency on an oscilloscope?

Because we are talking about 17.2MHz and lower XTALs, having a 100MHz scope is important because you want 5x the XTAL frequency on your scope where possible.

And because the XTALs we're talking about are full-sized CANs (not the 2-pin kind), they are active and therefore can be tested rather easily. Here's a schematic I quickly stole from the internet...

If you put your XTAL on a breadboard, it would be easy to add the 10nF capacitor across the supply voltage as shown above, but it's not absolutely necessary. It just makes things a teensy tiny bit better. And you technically don't need the CL output capacitor either. Just put your scope's probe hook on the TEST POINT, and put it's GND to GND. The longer your probes ground lead, the more noise you'll see on the scope. Some probes come with a special ground that looks like a spring at one end, and a needle at the other. It's very short and is good to use when possible. But unless you're experienced, I advise against it because if your little ground pops up and accidentally shorts on something, the end result wouldn't be pretty. But if you can safely and stably use the little ground on your probe, then it's always best to do that. Otherwise, just use the standard wire type ground on your probe and you'll still be able to verify if the XTAL is working or not.

BEWARE! If your XTAL is only 3.3V and you apply 5.0V to it, poof! You will kill it. But you shouldn't be buying 3.3v XTALs anyway. What we are talking about requires a 5.0v XTAL. So when you buy a XTAL, be sure to confirm the voltage with the seller, especially on AliExpress. These people sometimes make mistakes, so asking them more than once isn't being pushy.

 

[wottle]

Because we are talking about 17.2MHz and lower XTALs, having a 100MHz scope is important because you want 5x the XTAL frequency on your scope where possible.

And because the XTALs we're talking about are full-sized CANs (not the 2-pin kind), they are active and therefore can be tested rather easily. Here's a schematic I quickly stole from the internet...

View attachment 21771

If you put your XTAL on a breadboard, it would be easy to add the 10nF capacitor across the supply voltage as shown above, but it's not absolutely necessary. It just makes things a teensy tiny bit better. And you technically don't need the CL output capacitor either. Just put your scope's probe hook on the TEST POINT, and put it's GND to GND. The longer your probes ground lead, the more noise you'll see on the scope. Some probes come with a special ground that looks like a spring at one end, and a needle at the other. It's very short and is good to use when possible. But unless you're experienced, I advise against it because if your little ground pops up and accidentally shorts on something, the end result wouldn't be pretty. But if you can safely and stably use the little ground on your probe, then it's always best to do that. Otherwise, just use the standard wire type ground on your probe and you'll still be able to verify if the XTAL is working or not.

BEWARE! If your XTAL is only 3.3V and you apply 5.0V to it, poof! You will kill it. But you shouldn't be buying 3.3v XTALs anyway. What we are talking about requires a 5.0v XTAL. So when you buy a XTAL, be sure to confirm the voltage with the seller, especially on AliExpress. These people sometimes make mistakes, so asking them more than once isn't being pushy.

So I received the board and it was pretty rough.

One pad ripped off (I think it was already detached before I started cleanup. The larger oscillator had two pins that remained in the board when I removed it, so it is not salvageable. The smaller one also left one of its legs on the board when I removed it.

However, after cleaning, repairing the torn pad, and getting new caps and the new smaller oscillator installed, it is looking pretty good. I’m pretty hopeful I can get this thing working if the custom oscillator I got from AliExpress is correct.

I plan to put some hot glue on the cap and my bodge wire once I get the new oscillator installed. Then hopefully I can throw it into one of my LCs to test it. Appreciate all the help!

 

[wottle]

So, the aliexpress package got here today. The part was labelled as 17.234000 MHz, but no markings on voltage. The seller did confirm I wanted a 5v oscillator, so I was hopeful that was the case. I soldered it in, making sure the ground pin matched the ground through-hole on the board, and threw the card in my Performa 405. Once I got the right software installed to support the IIe Card, I plugged a FloppyEmu into the Y cable, launched the Apple IIe app, and it worked! I need to do a little more cleanup on the board as there are some vias by the PDS connector that still have some pretty bad corrosion. But I'll do that, add some hot glue to gold the caps and bodge wire in place, and I can get it sent back to its owner. Thanks @JDW for the help.



Also, if anyone in the US is looking for a custom oscillator like I did, here's the seller I used: https://www.aliexpress.us/item/3256...st_main.5.572f18026a1IGn&gatewayAdapt=glo2usa

Message them before hand and let them know what you need. They were very responsive and shipped it the same night.


So that was the good news.

The bad news is that I was able to use this repair card to confirm that the card I own is not working properly. I bought it on eBay from a seller claiming it was working, but was never able to get it to work. It would always fail to load ProDOS, no matter what disk I used, or floppyEmu, or a ProDOS hard drive image. I assumed I had something wrong with the software. I tried re-capping it. Still didn't work. But without a working card, I couldn't be sure. So it appears my card is bad, because when I swap it into the machine with a known good setup, it fails to load the program from the floppy. It looks like it is dropping into the BASIC command line. Anyone have thoughts? I'll probably start a new thread to troubleshoot that issue separately since I now know it is an issue with the card.

 

[JDW]

@wottle
This bad boy gives you bragging rights...

"My oscillator is more stable than yours!"

I dare say there's not another IIe Card on the planet that has a TCXO on it. The cards use run-of-the-mill oscillators that aren't bad, and the card is designed to accommodate their tolerances, but a TCXO is the cream of the crop when it comes to those metal can oscillators. And because they are so cheap on AliExpress, it makes no sense to buy a lesser type.

Glad you got that one card up and running!

I am no expert on the IIe Cards though. Recapping? Sure. Advice on oscillators? Yes. Knowing all the common problems that plague them and how to fix them? No. Same was true of my Macintosh Portable 5126. I could have recapped it myself, but I knew those leaky caps wreaked havoc on the PCB, so I decided to ask someone experienced with Portable repair to fix it, before it was eventually shipped to me in Japan. I asked Thomas of Amiga of Rochester to help me out, and he did. He fixed all the broken traces and got it up and running, even though there is no 5126 schematic available.

I realize that many folks in this hobby enjoy the hobby for the sake of repair. Will Jacobs of CayMac told me he doesn't get to have fun actually using vintage Macs so much because he's always repairing something, and he told me he actually likes it. So if you fall into that camp, you may be inclined to troubleshoot that card yourself, no matter how many days it may take. And that's perfectly OK. But I lack time and patience for that, and if you're like me, asking someone experienced with those cards may be prudent.

However, if the seller of the bad card told you it was working, that clearly isn't true based on your experience of now having a working card with which to compare. So it may be best to sort that out with the seller if you still are able to do that. Then again, I suspect the seller might just trash the card rather than spend time and money trying to get it repaired, and since those cards are no longer made, it would be somewhat of a loss (assuming it even can be repaired).

 

[wottle]

@wottle
This bad boy gives you bragging rights...

View attachment 21814

"My oscillator is more stable than yours!"

I dare say there's not another IIe Card on the planet that has a TCXO on it. The cards use run-of-the-mill oscillators that aren't bad, and the card is designed to accommodate their tolerances, but a TCXO is the cream of the crop when it comes to those metal can oscillators. And because they are so cheap on AliExpress, it makes no sense to buy a lesser type.

Glad you got that one card up and running!

I am no expert on the IIe Cards though. Recapping? Sure. Advice on oscillators? Yes. Knowing all the common problems that plague them and how to fix them? No. Same was true of my Macintosh Portable 5126. I could have recapped it myself, but I knew those leaky caps wreaked havoc on the PCB, so I decided to ask someone experienced with Portable repair to fix it, before it was eventually shipped to me in Japan. I asked Thomas of Amiga of Rochester to help me out, and he did. He fixed all the broken traces and got it up and running, even though there is no 5126 schematic available.

I realize that many folks in this hobby enjoy the hobby for the sake of repair. Will Jacobs of CayMac told me he doesn't get to have fun actually using vintage Macs so much because he's always repairing something, and he told me he actually likes it. So if you fall into that camp, you may be inclined to troubleshoot that card yourself, no matter how many days it may take. And that's perfectly OK. But I lack time and patience for that, and if you're like me, asking someone experienced with those cards may be prudent.

However, if the seller of the bad card told you it was working, that clearly isn't true based on your experience of now having a working card with which to compare. So it may be best to sort that out with the seller if you still are able to do that. Then again, I suspect the seller might just trash the card rather than spend time and money trying to get it repaired, and since those cards are no longer made, it would be somewhat of a loss (assuming it even can be repaired).

Unfortunately, the purchase was long enough ago that I don't think I have any recourse. And the seller may have done just enough testing to see that it booted into something, but not tried to boot from a ProDOS disk.

Yeah, if there were schematics, I probably would give it a shot myself, but I may have to bring in the big guns on this one. I don't have a good enough oscilloscope or the knowledge to know what to look for. I'll start a new thread for the troubleshooting of my card in case others in the future have similar symptoms. Maybe we can figure it out and publish the cause for others to self diagnose in the future.

Thanks again for your help in figuring out how to get a new oscillator. I definitely would never have thought to ask for a custom clock speed from AliExpress!

 

[SteveHere]

I have one of these cards that needs a new crystal, too, thanks!