Testing Google Photo insert due to bug

As of right now, Blogger is only showing 6 photos available for today for import from Google Photos, yet Google Photos shows 31 photos taken today. 

Yamaha YPT-300 keyboard - key fix

My Uncle Gus gave me a Yamaha YPT-300 keyboard for Christmas. He bought it for my late Aunt Judy. It has 1 broken key (low C) and was missing the sheet music rest. He also gave me a keyboard stand that was missing a screw at the bottom.

Otherwise is a pretty cool keyboard with a bunch of features: MIDI controls, built in speakers, 32 voice polyphony, ability to connect a sustain pedal, and at least 128 voices and beats, plus 4 built-in drumkits. Sound is definitely not bad. My bro and nephew and I had a lot of fun jamming on Christmas Eve.

Found and ordered the sheet music rest today ($25 including shipping on Full Compass) and also spent $25 for a replacement key set from Keyboard Kountry ($25 including shipping) .

So I will need to replace the low C key. Found some good YouTube videos on how to do this:

Video 1: https://youtu.be/q_oUbYPFTqk
Video 2: https://youtu.be/_uToVbDDVC0

There's a bit of yellowing on the keys, so I'm considering doing some Retrobrite peroxide treatment on them, we'll see how it goes.

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Ed Note 2024-01-19: I was able to complete the key replacement repair in September 2020, using the above videos for reference. It went pretty well, no major gotchas, and I took my own videos of the process. The key alignment was a tiny bit off, but not enough so to warrant additional replacement. Wasn't too hard to do. Never did the Retrobrite treatment although I'm sure it would help. 

BR-9 fixed

Finally fixed my Gibson BR-9 lap steel a few months ago. I was so tired of futzing with it, with no good results, so I took it to a local guy who builds his own guitars, he went through it in detail and found that there was an intermittent connection in the pickup coil, that somewhere inside the coil the wire broke. He worked to carefully unwind it to see if he could reconnect it, but the break was deep inside, so he sent it out to get re-wound. A non-vintage solution but better than having a broken lap steel!

In my research I found a really great web site and spreadsheet which lists impedance and other specs for these pickups:

https://courses.physics.illinois.edu/phys406/sp2017/Experimental_Results/Pickup_Data/Guitar_Bass_Pickup_Data.xls

Also learned from their course web site that the BR-9 pickups are easy to work on because the covers can be easily removed.

https://courses.physics.illinois.edu/phys406/sp2017/406emi_guitar_pickup_results.html

"P90-style pickups are interest here because they can be {non-destructively} taken apart, enabling the study of how these {lumped} parameters change as the pickup is put back together, one piece at a time!"
It works perfectly and still sounds great! Now at least it's reliable.

Fixing my BR-9

Another project for the list. My Gibson BR-9 lap steel has been really noisy, so I've been investigating the possible culprits.

Right now something is shorting out in the tone control, causing the tone control to act like a volume control. I thought this was the capacitor, but testing it out with the cap desoldered and bypassed with another capacitor still yielded the same problem.

So I ordered 2 new 500K pots, so I plan on rewiring the whole thing. Of course, for value purposes, I plan to keep all the original pots & caps.

The projects list

I have quite a list of little electronics projects to finish:

1. Build a new Champ Amp chassis: I have a board, components, transformers, pots, wire, etc. 
2. Build a Deluxe Amp clone
3. Finish "Old Ironsides"  (test transformers)
4. Repackage NPN Fuzz, and test with different components
5. Build GGG Shin-Ei Companion Fuzz kit
6. Build GGG Mini Mixer Kit
7. Build a few Craig Anderton EPFM projects

Boss HM-2 Repair - Part 3 (final)

So I got the HM-2 fixed, but it wasn't without its problems.

The pins on the DS-2 replacement pot are a little too short to get all the way through the board with ease. In addition, the replacement pot doesn't have board mounting tabs on the LH and RH sides, so the mechanical connection isn't as good. 

So first I unsoldered the old pot and saved it. 

Next I bent the pins carefully on the new with some pliers. Then I soldered the pot in at a shallow, slight angle, so that the pins could make a strong connection on the other side of the board. Finally I went to bend the pot flush with the board after it was soldered and I heard a crack: apparently the phenolic mounting wafer on which the pot is mounted cracked. I checked the pot values to make sure it was still working, and it was still in spec. I also spun the knob, and felt a tiny "tick", like a detent, in the action, about 1/2 way. 

Closed it back up, took it to the guitar lab and plugged it in, all good! I felt a little like the new pot didn't have the same range as the original; but then again I haven't use the paddle in many years so I can be sure. It seem like between 7 o'clock (zero distortion) and 9 o'clock, the sound goes from a heavy over drive to a mean growl. From 9 o'clock to noon, it gets funnier and deeper. From 12 o'clock to 5 o'clock though I can't tell much difference, I don't seem to hear much of a difference in sound. That may be because I was testing it out on my DG stop and it was very oversaturated.

The replacement knob is slightly brighter orange than the original 3 knobs, but that may change with time & grime.

Happy to have it all back together and working. 

Screaming Bird fix

I got my EH Screaming Bird pedal fixed today. Took some mucking around, developing a wiring diagram, testing... Jack Ormans LPB-1 schematic was the closest to the actual values in my Screaming Bird; the other common schematics used different transistors with  different values. 

Found some wiring photos of other LPB1 and Screaming Bird online and was able to deduce and test wiring through trial and error. 

Here was it in the testing stage, wiring here is wrong, but pretty close:

I had to replace a missing DPDT switch, which I found at Radio Shack a few weeks ago...nice that thy still carry parts!

Here was the final wiring diagram that worked, so I drew it up:

I think it's interesting that +9V runs to the Jack sleeve (traditionally ground!). The values in the diagram above are the actual ones I observed/measured. As in the other schematics I've seen, you could easily substitute the two caps for .002uF, or other more convenient values. 

Looks nice buttoned up, and sounds nice too!