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Post by spetersen on Nov 18, 2019 1:20:41 GMT
The pi zero wireless does not do wireless and Bluetooth all together that well according to what I read, I was thinking of adding Bluetooth speakers to mine, they suggested that either a separate Bluetooth or wireless USB adapter solves the problem.
Because the back of the wallbox isn't finished, I just mounted a small enclosure to the back, and I also mounted rubber feet underneath to it can sit on a table, with the back against the wall..
Changing to led bulbs will save 1/2 an amp of current also. The pi zero has plenty of power and memory to run the wallbox, I'm only at 20% now while playing, IR does not take much either.
The zero has capabilities to play HD video over HDMI, so it isn't even taxed running my box headless.
There is one thing you should know, the zero audio is "OK" it would sound better through HDMI or a DAC, there are small noises in the background which can be heard with the amp turned up, without the music playing
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sooner
Full Member
Oklahoma
Posts: 117
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Post by sooner on Nov 18, 2019 6:01:55 GMT
Scot - You might look into a toroidal transformer. They're quite a bit more expensive but smaller than standard square transformers.
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Post by spetersen on Nov 19, 2019 9:30:50 GMT
I checked my box, while it is playing, and at idle it draws 9 watts, it has been converted to led, when selecting it draws about 22 watts, which says that the 24v transformer needs to deliver about an amp while selecting.
Some pics of the one I built for a friend
The pics showing the color change after pressing V8 Under U8 red and blue I put 100 songs in each "slot", it plays all day without repeating once.
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Post by spetersen on Nov 19, 2019 9:45:54 GMT
A couple more pics. The buttons are credit, reject, and the lever switch is freeplay. The wire hanging is waiting for a switch, which will be to shutdown the Pi gracefully. The volume knob and amp is missing due to an unfortunate accident, I was trying to reduce some hum, and I charged a cap to 35v, and accidentally touched the 5v power without discharging it, and fried the pi, a usb drive and the amplifier. That $20 dollar bill went up in smoke! The power supply. and the interface board survived.
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ScotK
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Posts: 113
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Post by ScotK on Nov 19, 2019 14:20:09 GMT
The pi zero wireless does not do wireless and Bluetooth all together that well according to what I read, I was thinking of adding Bluetooth speakers to mine, they suggested that either a separate Bluetooth or wireless USB adapter solves the problem. Because the back of the wallbox isn't finished, I just mounted a small enclosure to the back, and I also mounted rubber feet underneath to it can sit on a table, with the back against the wall.. Changing to led bulbs will save 1/2 an amp of current also. The pi zero has plenty of power and memory to run the wallbox, I'm only at 20% now while playing, IR does not take much either. The zero has capabilities to play HD video over HDMI, so it isn't even taxed running my box headless. There is one thing you should know, the zero audio is "OK" it would sound better through HDMI or a DAC, there are small noises in the background which can be heard with the amp turned up, without the music playing Yeah, the wireless was another reason I was going for the Pi 4. I've used a few Pi 3's and have not been disappointed yet. I'm not likely to get a ton of range out of the bluetooth or wifi due to the metal casing but I'm hoping I get at least a few feet. I know there are USB DACs that I could get if the audio bothers me. I don't think I'll be getting great audio out of the built in speakers anyway, so I was going to take a wait-and-see approach to the audio quality. That's another reason i wanted bluetooth too, if I wanted better sounding audio I could just flip on the stereo which would bypass the amp and speakers and should result in much better audio quality. |
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ScotK
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Post by ScotK on Nov 19, 2019 14:28:36 GMT
Scot - You might look into a toroidal transformer. They're quite a bit more expensive but smaller than standard square transformers. Good idea, but from the specs it wouldn't save much space. The 5v supply I was intending to use was almost the same size as the Pi. The 5v buck transformer is significantly smaller, it should give me the space I need to mount the Pi and the transformer inside the case. |
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ScotK
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Posts: 113
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Post by ScotK on Nov 19, 2019 15:00:58 GMT
So if the wallbox draws 1A of power, that leaves 1A for the rest of the 5vDC equipment. I don't know how to do the actual calculation but my estimate is after conversion to 5v it should be able to provide about 5A. The Pi 4 is 3A max, the amp is .6A (3 watts), leaving around 1.5A at 5v free. The transformer is 2.08A at 24vAC, so that should leave me with somewhere around 0.4 amps free at 24v if everything is pulling maximum power draw. Not a lot of overhead left on the 24v transformer but I'm not going to be hitting maximum draw all the time either.
I could swap out a Pi4 with a Pi3 if my power estimates are off. That would save 1A at 5v, but by the time you convert that to 24vAC that's not much. I have a 2amp fuse on the transformer, if I start blowing that I'll have to look for some power savings. Convert to LED maybe.
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ScotK
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Posts: 113
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Post by ScotK on Nov 19, 2019 15:30:56 GMT
OK, in reading about the power consumption and heat produced by the Pi4 I think I'll be repurposing the Pi4 to use around the house and swapping in a Pi3. That'll save me power, quite a bit of heat from the reviews of the Pi4, and no downsides that I can see other than going down a compatibility level in bluetooth.
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Post by spetersen on Nov 19, 2019 16:56:56 GMT
The 9 watts of power included the Pi and amplifier, the 22 watts as well
"I'm not likely to get a ton of range out of the bluetooth or wifi due to the metal casing but I'm hoping I get at least a few feet."
Actually mine is completely encased in metal, and I can pick it up all over the first floor.
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sooner
Full Member
Oklahoma
Posts: 117
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Post by sooner on Nov 20, 2019 3:13:22 GMT
I don't know how to do the actual calculation but my estimate is after conversion to 5v it should be able to provide about 5A. If I understand correctly... I went through that a similar exercise recently trying to figure out what size fuse I needed on the 120V side of the transformer. I believe the power on either side of the transformer will be the same (assuming 100% efficiency) so with 24V @ 2 amps you have 48 watts on the (24V) side. On the 5V side at 48 watts you would have 9.6 amps. Actual available current on the 5V side would be a little less than 9.6V so probably about 9 amps assuming 95% efficiency. At least that's my theory... :-) Here's a handy Ohm's Law calculator: www.sengpielaudio.com/calculator-ohm.htm |
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ScotK
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Post by ScotK on Nov 22, 2019 18:29:27 GMT
Posting my first attempt at a wiring diagram. Still waiting on a few more components, but I've started mounting and wiring stuff inside the wallette. Attachments:
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Post by Ron Rich on Nov 23, 2019 0:18:06 GMT
Hi Scott,
It AIN'T a "Wallette"! Wallette is the ™ of Rowe, not Seeburg. Seeburg's ™ was "Consolette" and Wall O Matic.
Ron Rich
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sooner
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Oklahoma
Posts: 117
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Post by sooner on Nov 23, 2019 4:37:59 GMT
ScotK - Impressive and most of it way over my head.
It looks like all coins will be treated equally as far as credit goes. Will this system allow for multiple credits to be established? Will you be able to be able to set up different prices for singles vs. albums?
I also noticed that the volume buttons use both series and parallel resistors so total resistance is not proportional to sound level. Will that be a problem?
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Post by spetersen on Nov 23, 2019 12:19:12 GMT
Does the buffered in 2, supply 5v to the optoisolator? The "signal" at the blue terminal is a pulsed ground with reference to the frame. The buck converter I used was 35v DC to 5v DC(adjustable for voltage and current) I rectified the 24vac to DC and fed the converter
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ScotK
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Post by ScotK on Nov 25, 2019 12:42:18 GMT
Hi Scott, It AIN'T a "Wallette"! Wallette is the ™ of Rowe, not Seeburg. Seeburg's ™ was "Consolette" and Wall O Matic. Ron Rich Lol... thanks for the correction Ron! |
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