A bit cheaper from RS components.
https://uk.rs-online.com/web/p/switchin ... rs/6727124
Mark will advise where to get the caps no doubt but they are not essential to make things work if you just want to see the result as they are there just to get rid of high frequency spikes in the power supply plus add some stability to same and so preferable but not essential.
I don't use them at all but then I am the king of the bodgers and best to follow his sound advice.
Runs and hides so as not to incur Mark's wrath.
Case considerations
- 1024MAK
- Posts: 5118
- Joined: Mon Sep 26, 2011 10:56 am
- Location: Looking forward to summer in Somerset, UK...
Re: Case considerations
The extra capacitors are the blue ones. The brown disc capacitor is a part originally fitted by Sinclair. The position of this varies between different boards, so it may not be in the same position on your board. It may also be a different style.
Back to the blue capacitors, they are 100nF multilayer ceramic types. They are rated at 50V, but 100V types are okay as well. They come with the leads in two pitch spacings. 2.5mm/2.54mm and 5mm/5.08mm, I used one of each. These may also be classified as Radial Ceramic. I got mine from Rapid many years ago, the particular brand I bought has been discontinued, but all electronic suppliers should be able to offer equivalents.
For example, from RS, these are suitable:
Vishay 100nF Multilayer Ceramic Capacitor MLCC 50V dc ±10% , Through Hole K104K15X7RF53H5,
RS Stock No.: 852-3270
Link https://uk.rs-online.com/web/p/mlccs-mu ... rs/8523270
Vishay 100nF Multilayer Ceramic Capacitor MLCC 50V dc ±10% , Through Hole K104K10X7RF53L2,
RS Stock No.: 852-3261
Link https://uk.rs-online.com/web/p/mlccs-mu ... rs/8523261
There are also various models from RECOM, as they have improved their designs over the years.
The RECOMs are available in various ratings. The type we are discussing have a 5V DC output are typically rated at a maximum current output of 1A. But other current outputs are available.
I've not done the calculations, but, yes, I believe it should be possible to run a ZX81, and a Pi Zero. Yes, you should be able to run a 5V fan as well. Just not sure you actually need a fan if you are using a RECOM. Without the 7805 and it's heatsink, the board will run much cooler.
Mark
Back to the blue capacitors, they are 100nF multilayer ceramic types. They are rated at 50V, but 100V types are okay as well. They come with the leads in two pitch spacings. 2.5mm/2.54mm and 5mm/5.08mm, I used one of each. These may also be classified as Radial Ceramic. I got mine from Rapid many years ago, the particular brand I bought has been discontinued, but all electronic suppliers should be able to offer equivalents.
For example, from RS, these are suitable:
Vishay 100nF Multilayer Ceramic Capacitor MLCC 50V dc ±10% , Through Hole K104K15X7RF53H5,
RS Stock No.: 852-3270
Link https://uk.rs-online.com/web/p/mlccs-mu ... rs/8523270
Vishay 100nF Multilayer Ceramic Capacitor MLCC 50V dc ±10% , Through Hole K104K10X7RF53L2,
RS Stock No.: 852-3261
Link https://uk.rs-online.com/web/p/mlccs-mu ... rs/8523261
There are also various models from RECOM, as they have improved their designs over the years.
The RECOMs are available in various ratings. The type we are discussing have a 5V DC output are typically rated at a maximum current output of 1A. But other current outputs are available.
I've not done the calculations, but, yes, I believe it should be possible to run a ZX81, and a Pi Zero. Yes, you should be able to run a 5V fan as well. Just not sure you actually need a fan if you are using a RECOM. Without the 7805 and it's heatsink, the board will run much cooler.
Mark
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer later in the year.
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer later in the year.
Re: Case considerations
Well, I've been watching the Pi0 and it's only pulling roughly 0.2A. Give or take a little bit either side.
With the Murara drop in coming in at 1.5A, should that be enough to run the zeddy and the PiZero?
Or am I overlooking something?
With the Murara drop in coming in at 1.5A, should that be enough to run the zeddy and the PiZero?
Or am I overlooking something?
All that I've learned - https://msknight.com/bbc/index.html#zx81
- 1024MAK
- Posts: 5118
- Joined: Mon Sep 26, 2011 10:56 am
- Location: Looking forward to summer in Somerset, UK...
Re: Case considerations
I've checked elsewhere, and it appears that the maximum running current for a Pi Zero or a Pi Zero W is 240mA.
So yes, should be no problem, even with a 1A DC/DC converter.
The least expensive RECOM at RS is this one:
Recom Switching Regulator, Through Hole, 5V dc Output Voltage, 8 → 28V dc Input Voltage, 1A Output Current,
RS Stock No.:144-6290.
Link https://uk.rs-online.com/web/p/switchin ... rs/1446290
Mark
So yes, should be no problem, even with a 1A DC/DC converter.
The least expensive RECOM at RS is this one:
Recom Switching Regulator, Through Hole, 5V dc Output Voltage, 8 → 28V dc Input Voltage, 1A Output Current,
RS Stock No.:144-6290.
Link https://uk.rs-online.com/web/p/switchin ... rs/1446290
Mark
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer later in the year.
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer later in the year.
- 1024MAK
- Posts: 5118
- Joined: Mon Sep 26, 2011 10:56 am
- Location: Looking forward to summer in Somerset, UK...
Re: Case considerations
For types that have right angle pins:
RS PRO Switching Regulator, PCB Mount, 5V dc Output Voltage, 8 → 36V dc Input Voltage, 1A Output Current,
RS Stock No.: 193-4025.
Link https://uk.rs-online.com/web/p/switchin ... rs/1934025
Recom Switching Regulator, Through Hole, 5V dc Output Voltage, 6.5 → 32V dc Input Voltage, 1A Output Current,
RS Stock No.: 672-7149
Link https://uk.rs-online.com/web/p/switchin ... rs/6727149
Mark
RS PRO Switching Regulator, PCB Mount, 5V dc Output Voltage, 8 → 36V dc Input Voltage, 1A Output Current,
RS Stock No.: 193-4025.
Link https://uk.rs-online.com/web/p/switchin ... rs/1934025
Recom Switching Regulator, Through Hole, 5V dc Output Voltage, 6.5 → 32V dc Input Voltage, 1A Output Current,
RS Stock No.: 672-7149
Link https://uk.rs-online.com/web/p/switchin ... rs/6727149
Mark
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer later in the year.
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer later in the year.
Re: Case considerations
Does that put the Murata, at 1.5A, as a better choice then? I mean, half an amp more is a little better than pushing the limit of the 1A output of the others you've listed? Or am I (as usual) missing something?
https://www.retroleum.co.uk/result.php? ... es+7805%29
https://www.retroleum.co.uk/result.php? ... es+7805%29
All that I've learned - https://msknight.com/bbc/index.html#zx81
- 1024MAK
- Posts: 5118
- Joined: Mon Sep 26, 2011 10:56 am
- Location: Looking forward to summer in Somerset, UK...
Re: Case considerations
The Murata type is fine.
Mark
PS your link is not working. But I know the one you mean.
Mark
PS your link is not working. But I know the one you mean.
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer later in the year.
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer later in the year.