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Ron, not exactly sure which terminal on Q100 is the drain, but I do have continuity from LCD pin 16 to the Q100 terminal that is on the right side on its own. The other two terminals on Q100 do not have continuity with LCD pin 16. Also, none of the terminals on Q100 has continuity with any other terminal on Q100. On closer inspection of C100, it does look a little suspect with a small piece missing off a corner. This could have been related to my efforts to make sure all soldering was solid. I'll follow your advice to remove C100 over the weekend. Should I look for any change in the backlight on removal of C100 ? I imagine I can find a replacement fairly easily, looks to be 2.2uF.

Jeremy

Broken powdered iron toroids can usually be glued together without a major effect on their inductance. (That doesn't work as well for ferrite toroids.) -0 toroids (the?pinkish ones in the QMX) are just round coil forms (they don't contain metal) so they can be glued together with no effect at all. But if you do decide to buy some...

The powdered iron toroids that are ubiquitous in ham radio projects are made by Micrometals. That company has never been friendly about selling in small quantities or making their products available through major ham-friendly distributors such as Digikey and Mouser, so we're dependent on a few companies that sell them to individuals. The ferrite toroids (the ones that are metallic looking rather than painted) mostly come from Fair-Rite, and those are available from distributors.

These days, the best source of toroids is kitsandparts dot com, which was run for many years by?Dieter "Diz" Gentzow W8DIZ (SK)?and now run by Mike Maiorana KU4QO. But indeed, most of them are sold in bags of 25. Larger and more expensive toroids are sold in smaller quantities. Hans bought his toroids from Kits and Parts for many years, until his quantities got large enough to be able to order directly from Micrometals.

The first source of toroids that hams used was Amidon Associates. They're still in business and they sell individual?toroids. But their prices are much higher. For example, a single T37-6 costs $0.95 from Amidon, but a bag of 25 of them from Kits and Parts is $6.?

CWS Bytemark is another company that sells toroids. Their prices on single toroids are better than Amidon's; they normally?sell a single T37-6 for $0.55, but it's currently on sale for?$0.17. I haven't heard of any hams buying from them, so I have no idea what their quality of service is, or whether they are selling Micrometals toroids or toroids from another supplier. They have a $25 minimum order, so you'll have to order a bunch of stuff from them to reach that.

The G-QRP club sells components to its members, including bags of 5 toroids. Getting them shipped from the UK to the US might be problematic at this time. G-QRP membership costs about $20 per year for people in the US, and includes four quarterly issues of SPRAT, their magazine.

On Sat, May 10, 2025 at 12:05?AM Chuck Harris via <cfharris=[email protected]> wrote:

Most cores can be glued back together with a tiny
drop of cyanoacrylate glue, and a little bit of care.

Some, like the pink ones are just place holders for the
wire, so they can be glued too.

-Chuck Harris, WA3UQV


On Fri, 09 May 2025 14:01:43 -0700 "ke2bks via "
<ke2bks=[email protected]> wrote:
> Hello All,
> In an unfortunate accident, I dropped my QMX+ pcb that I was working
> on and broke few of the toroids. Visually, other toroid looks ok. Can
> these broken toroids be salvaged? I Is there any website/ store in US
> that I can buy the new ones in small quantities( like 2-3 ) instead
> of buying 25 pcs? What other alternatives can I try to substitute
> these components? Your help is appreciated. 73 Subash KE2BKS
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