LimeSDR learning curve

LimeSDR is complex piece of hardware, therefore some of us “old folks, 50+” may have some difficulty during our learning curve, all up to level of useful use in accordance to our needs.

Lime is my SDR No6. (2xSDRPlay, 1xRTL-SDR, 1xFR24dedicatedSDR, 1xAISdedicatedSDR) all used both on Linux, RPI and Win. Personal experience, ham since mid '70ties, electronics and aviation background, 20+years in IT too, from programing to HW distribution and repairs.

And with all that on quick start I needed assistance from Marty :smiley: because I was not patient enough to read bellow to chapter 4. :stuck_out_tongue:

Lime is nice piece of hardware, please look at it like nice learning tool not like some piece of consumer electronics with on/off switch only.

Now going to resolve cooling on my LimeSDR, at the moment that is my major concern :wink:

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Djani,

Don’t feel alone - I’m one of those ‘over 50’ guys, too…and I’m JUST as impatient…! :smiley: !!!

Good to hear that your LimeSDR is alive and well - have fun and keep all of us advised when you need help.

73 de Marty, KN0CK

[quote=“9a4db, post:1, topic:866, full:true”]
Lime is nice piece of hardware, please look at it like nice learning tool not like some piece of consumer electronics with on/off switch only. [/quote]

Yes, and something that a few need to remember here. But there’s lots of activity to make it work well.

I have been looking into different cooling ideas. I will be designing my own case. Will definitely place it edge-on with the long side horizontal so the board faces can dissipate heat more readily. Still looking at ways to transfer heat externally so the case can be sealed.

Regarding the thermal management
Here just doing some tests.
Metal Al box approx footprint of 2,5 x LimeSDR size
38 mm H
120 mm W
190 mm L
Lime mounted inside with approx 8 mm air gap bellow and 28 mm above.
Plastic board spacers replaced with brass, edges fixed to box with some thermal silicon.
Box closed and sealed for RF.
During the test box turned in position which allow internal air to circulate on both Lime sides,
on longer run air inside box and Lime board edges are on 35 C average.
Still have problem with surfaces of both major chips going up to 55 C

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Rx 1 W port modified, coil removed.
Unit is useful now for 7 MHz band… and above. Air band improvement too.
3,5 MHz not good enough
All using my ferite antenna resonant from 1,5 to 8,5 MHz, no preamp

LimeSDR RX1W modified

SDRPlay RSP1

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Tip, use of modified Rx1W for HF -> only with band pass filters and FM band trap…

On the other hand my favor local Air Band ATIS is going nice on 1/4 lambda inside:

What do think the allowable maximum temperature should be? PS. I’m 132 years old!

Like to keep mine around 40 C or bellow if possible…

Just ordered one -> http://lna4hf.blogspot.hr/
from OM Adam 9A4QV… must help a bit.
I am happy user of his LNA4ALL too…

Creative mess during the testing :smiley:

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My box details. At the moment only one N connector on the top.

My last cooling setup consist of above Al cast box closed, with:
one small turbine fan blowing inside on major chips,
plus
one big fan and cooler on the box top

Now Lime Suite is reading 42-43 C on long RX run FM broadcast music
outside temp 24-27 C, room 21 C
Guess I am ready for Ubuntu phase and some TX testing…
73

Some CW seen on 3,5 MHz LimeSDR
Rx1_W modified, 20 cm ferrite loopstick antenna (resonant & band selective 1,5 to 8,5 MHz) no preamp

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So, in case you like to keep your Lime around 35 C during the high loads,
this is my solution ->

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Box from the outside…

That should keep it cool. Try not to achieve lift-off!

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Busted…I am in vertical aviation, you know :smiley:

Someone asked me to compare LimeSDR with SDRPlay RSP1
Here are some screens, runing on the W10, same antenna / end feed with 1:9 transformer,
through FC700 manual antenna tuner, and RF splitter with RF and spike protection.




So can you recognize which one is Lime or RSP1 :smiley: / without looking on the bottom left…

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Hello,

I am new to SDR and HAM. From my LimeSDR I have managed to tune the local FM stations using simple telescopic antenna, and this is pretty much all I have managed to get from the whole spectrum range with LimeSDR.

Can you guys give me some pointer about the room antenna, frequency and demodulation type I have to use in SDR Console to hear something else :slight_smile:

Thanks
Dimitar