New sdr computer.

Analoguesat

Analoguesat

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So having got a bit fed up with my little Dell netbook sitting on the window sill with the 360R software on it and a second old laptop in the window alcove with the wxsat software on it Ive decided to bite the bullet and set up a solitary midi tower which will hopefully combine the two rigs. This has to be done as cheaply as possible so Ive been raiding my bits boxes, old hard drives and derelict old computers towers to see what salvageable.

An Asus mini motherboard with an i3 processor looks promising, and Ive found 8GB of ram to put in it. It powers up find and to begin with Ive found a 500GB hdd to pair with it. The old cases are over 10 years old, battered and Ive decided to buy a cheap case to mount this in. I had been hoping to reuse an old Dell 5150 tower but I discovered that it doesnt have the motherboard rectangular "cutout" for the ports - its only got holes stamped through the chassis - so no fitting a different motherboard in it :-(

Im also wanting to mount as much of the sdr gubbins as possible internally and Ive got a semi half baked idea for that which I will detail later..

The new case is a CTI Goblin - 30 quid from Amazon

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There is a new power supply on order as the old ones are all very tired The case doesnt have the side green led fan on it as bought (thank goodness!) but I'll be putting a fan in the side or the back to improve airflow (from the junk box if I can find a suitably quiet one in there) Pics to follow of the build much as Vipersan did a couple of years ago. Still awaiting bits to arrive so the project will stretch out over the next couple of weeks or so.
 
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What bits do you need, put a list up...
I have boxes of PC parts and i'm sure others do on here too.
 
What would you guess is a minimum specification on a reasonable SDR desktop, I have a couple of complete Dells / HPs lying around, but the space in the office and under the table is at a premium.

Based on what Evan mentioned, an older tower with proper 'old school' Faraday screening throughout might be better than the modern towers with poly carbonate see through windows and flashing lights, though it was a few months ago, perhaps things have improved noisewise out there.
 
Channel Hopper said:
What would you guess is a minimum specification on a reasonable SDR desktop, I have a couple of complete Dells / HPs lying around, but the space in the office and under the table is at a premium.

Based on what Evan mentioned, an older tower with proper 'old school' Faraday screening throughout might be better than the modern towers with poly carbonate see through windows and flashing lights, though it was a few months ago, perhaps things have improved noisewise out there.
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Not meaning to answer for AS, but just from my experience.
I'd consider second gen Intel i Series to be a good place to start, some first gen will be fine.
Nothing has really progressed that much over the years.
 
It was a cit vantage case that started to melt. Otherwise it looks like that should be a nice little rig for sdr.
 
Chris1979 said:
It was a cit vantage case that started to melt. Otherwise it looks like that should be a nice little rig for sdr.
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:eek:Was that a cheap PSU it came with
 
This case is all steel apart from the front cover decorative panel. I cant see the point of polycarbonate windows - this isnt going to be a thing of beauty its a workhorse. I'll see how easy it is to replace that front led fan as well to reduce the internal rfi
Channel Hopper said:
What would you guess is a minimum specification on a reasonable SDR desktop, I have a couple of complete Dells / HPs lying around, but the space in the office and under the table is at a premium.
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From my experience you dont want anything more than about a decade old - my elderly Dell Dimension 5150 desktop (at least 12 years old) wont run the Zadig driver swapper. My underpowered little Dell netbook which is around 7 years old runs the plane tracking system perfectly but I dont think it would cope with the demands of sdr#

My wxsat system currently runs on a cast off i3 laptop with 4GB ram and runs sweetly. The new Frankenstein computer will be run headless - if you havent tried this have a look at tightvnc. Then you can put the sdr computer in a corner out of the way. You can mix & match the 32 & 64bit versions across the computers no problem. Then remote control the others from whatever your main computer is. Dead easy to set up and get running.
 
Don't mount the SDR receiver dongle inside the case, it tends to pick up a ton of RF hash and junk from the PC, thats why I shielded mine, I have a very low noise floor but I still get junk from the PC, I may try a 3 meter active USB extension to move it further away from the PC.
 
Analoguesat said:
Not sure yet - Im making this up as I go along! :-rofl2
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What's the board model and actual CPU?
The 8GB Ram you have, is that a single stick or a pair of 4GB sticks?

And I have quite a few SSD's here in my drawer if that's something you need.
 
RustySpoons said:
What's the board model and actual CPU?
The 8GB Ram you have, is that a single stick or a pair of 4GB sticks?

And I have quite a few SSD's here in my drawer if that's something you need.
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Dont know at the moment - a lot of my computer stuff got shoved into store prior to the house move to get it all out the way - I need to get it all back here to have a proper look! 2x4GB sticks of ram though.

If this build goes well I shall do another one to replace the tired beat up Dell 5150 I use every day. That one will be at least an i5 though and have 16GB ram.
 
Terryl said:
Don't mount the SDR receiver dongle inside the case, it tends to pick up a ton of RF hash and junk from the PC, thats why I shielded mine, I have a very low noise floor but I still get junk from the PC, I may try a 3 meter active USB extension to move it further away from the PC.
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Agreed, all my SDRs are now connected directly to the distro system I have to switch antennas to each SDR and then connected to the PCs using Volutz USB cables, there's been an noticeable reduction in the noise floor and sprogs since switching to this arrangement.

As for PC power it really depends on what the SDR is and how it will be used. My original RTL dongle ran on a dual core P4, Airspy needs i3 or AMD 8 core with a decent USB3 port (not Asus) to record 10MHz IQ files. The new Elad S3 will probably require an i7 and large amounts of disk space if the full 20MHz width is to be recorded.
 
First pic of the build. The psu will go over on the right when it arrives. The graphics card came out of the scrap Dell Dimension 5150 I had lying around. Im not convinced about the mini motherboard due to lack of expansion capabilities but its been lying around for ages looking for a new role in life so it will do to begin with until something better comes along.

Ive found a usb expansion card in the junk box this evening which connects via a header cable and there is a suitable header connection on the mobo so that will be going in.

The black cable is the usb3 connection - this mobo does not support usb3 so its ziptied out of the way for the time being.

sdrcomp.webp
 
Analoguesat said:
This case is all steel apart from the front cover decorative panel. I cant see the point of polycarbonate windows - this isnt going to be a thing of beauty its a workhorse. I'll see how easy it is to replace that front led fan as well to reduce the internal rfi


From my experience you dont want anything more than about a decade old - my elderly Dell Dimension 5150 desktop (at least 12 years old) wont run the Zadig driver swapper. My underpowered little Dell netbook which is around 7 years old runs the plane tracking system perfectly but I dont think it would cope with the demands of sdr#

My wxsat system currently runs on a cast off i3 laptop with 4GB ram and runs sweetly. The new Frankenstein computer will be run headless - if you havent tried this have a look at tightvnc. Then you can put the sdr computer in a corner out of the way. You can mix & match the 32 & 64bit versions across the computers no problem. Then remote control the others from whatever your main computer is. Dead easy to set up and get running.
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OK, I understand the part about modern processing being streets ahead of the Phenom/Xeon four core, and perhaps this combines with a lot of RAM helps. But is SDR all about processing power for the best imagery ?
Does a modern graphics card make up for a deficiency in the number crunching ability. Would having a server system running dual / matched processors do OK, or is SDR like gaming, where lightning fast response is about the only requirement ?
 
Analoguesat said:
First pic of the build. The psu will go over on the right when it arrives. The graphics card came out of the scrap Dell Dimension 5150 I had lying around. Im not convinced about the mini motherboard due to lack of expansion capabilities but its been lying around for ages looking for a new role in life so it will do to begin with until something better comes along.

Ive found a usb expansion card in the junk box this evening which connects via a header cable and there is a suitable header connection on the mobo so that will be going in.

The black cable is the usb3 connection - this mobo does not support usb3 so its ziptied out of the way for the time being.

View attachment 117259
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You have a lovely ITX board there, you could have utilised that in a really nice small case that would have fitted everything in for very little money.
Just snip the legs on the LED's and pull them out and any wiring thats not needed. Unless you have spare fans.


Channel Hopper said:
OK, I understand the part about modern processing being streets ahead of the Phenom/Xeon four core, and perhaps this combines with a lot of RAM helps. But is SDR all about processing power for the best imagery ?
Does a modern graphics card make up for a deficiency in the number crunching ability. Would having a server system running dual / matched processors do OK, or is SDR like gaming, where lightning fast response is about the only requirement ?
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Depends on the SDR Client software, not all will use the GPU for number crunching, SDR Console will use nVidia Cuda cores though, mainly CPU is most important. And that depends on what the bandwith is on the SDR device. If it's a RTL type SDR then a potato is powerful enough to resolve its I/Q data. If its something with higher bandwith and you are using various software then you need something powerful. But Powerful can be a gen 1 i5/i7. Even the old Gen 1 i7 2600K is Mega Powerful.
 
You just need enough grunt to run the programme. My Dell current desktop is an ancient 3.4GHz Pentium4 - this is too elderly to run even the Zadig drive swapper

These are the specs of my i3 lappie which happily runs the wxsat stuff.

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Pretty low end stuff in use here. Wxtoimg isnt particularly taxing when doing its onboard image processing. It'll do the 5 or 6 post pass processing pictures Ive got currently chosen in the programme in 30-40 seconds. If you get two passes immediately after each other its also intelligent enough to queue them, record the passes then do the post processing on the two recorded passes whilst waiting for the third pass.


If you have an old clunker lying around thats less than 10 years old give it a try - it'll probably work :D


To be honest the only reason Im putting the graphics card in my new sdr build is that its a handy place to keep it especially if I decide to purpose that computer in the future!
 
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RustySpoons said:
You have a lovely ITX board there, you could have utilised that in a really nice small case that would have fitted everything in for very little money.
Just snip the legs on the LED's and pull them out and any wiring thats not needed. Unless you have spare fans.
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The case is a bit bigger than I was expecting to be honest. But its fine even if the mobo does look rather silly cowering down in its corner. Plenty of scope for changing things in the future, adding extra drives, swapping the mobo for a bigger one. Ive got a few old 160/320GB hdd's lying around that I can install for added storage.

Ive had to find a wifi dongle from the junk box as Ive realised there is no ethernet connection where this computer will ulitimately be sitting!
 
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