Portsdown boxing/build thread
Re: Portsdown boxing/build thread
Hi Gareth
You might want to consider a hardware shutdown button: https://wiki.batc.org.uk/Portsdown_hard ... e_shutdown
Dave
You might want to consider a hardware shutdown button: https://wiki.batc.org.uk/Portsdown_hard ... e_shutdown
Dave
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Re: Portsdown boxing/build thread
In touch-screens I trust But yes, I have that fitted direct to the socket on the expansion board so could shift that and make a nice little shielded feature of it too with LED combined.
Gareth
Gareth
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Re: Portsdown boxing/build thread
That's filled the gap
Gareth-
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Re: Portsdown boxing/build thread
Front panel done Just got to wire it all up now.....
GarethRe: Portsdown boxing/build thread
Hi Gareth
Looks like your printer has been working overtime
You could add audio out, which I use when I stream to Portsdown
73
Nick
Looks like your printer has been working overtime
You could add audio out, which I use when I stream to Portsdown
73
Nick
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Re: Portsdown boxing/build thread
Sorting out a linear power supply today and work on the back panel. Using a LM338 with 13.8 as Vin (less 0.4 via a 10 amp schottky diode for reverse polarity protection). Test run with a load of 1.07 amps gives a steady state heatsink temperature of 52 Degrees C in a warm room, still air. Testing my RPi3B+ and it draws a max of 0.7 amps. The various peripherals are not going to add up to another 300 mA so I thinks its good to go. Bigger heatsink can easily be subbed-in if advice is to keep it cooler.
In pursuit of 'electrical silence' as far as possible. Case is plastic except front and rear panels, so not much screening as-is.
Gareth.
In pursuit of 'electrical silence' as far as possible. Case is plastic except front and rear panels, so not much screening as-is.
Gareth.
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Re: Portsdown boxing/build thread
Thanks for reminding me Nick, I'll be putting a small audio amp and speaker in there somewhere to save too many external leads Probably on the lid if I can find my mylar cone units I bought about 20+ years ago
Gareth
Gareth
Re: Portsdown boxing/build thread
I use PC speakers powered from one of the USB port of Pi.
There is plenty of volume.
73
N
There is plenty of volume.
73
N
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Re: Portsdown boxing/build thread
Just tested this: https://www.ebay.co.uk/itm/PAM8302-2-5W ... 2749.l2649 very adequate when fed with line level. Runs well on 3.3 or 5 volts.
Less than a £1 each delivered. With a mute function. Progress
Less than a £1 each delivered. With a mute function. Progress
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Re: Portsdown boxing/build thread
And onwards to including the attenuator (PE4302) which is directly connected to the output board input with a male/male SMA.
The data sheet says its rated for +30dBm which = 1 watt. So is anyone running one of the many 50 ohm in/out amps that are around on eBay before their attenuator? It would seem the best place to put in a bit more...
Thoughts and suggestions welcome.....
Gareth
The data sheet says its rated for +30dBm which = 1 watt. So is anyone running one of the many 50 ohm in/out amps that are around on eBay before their attenuator? It would seem the best place to put in a bit more...
Thoughts and suggestions welcome.....
Gareth