biggest problem is the milled case and of course the soldering. ... any ideas?
This design seems good for the LimeSDR!
Driver PA up to 1W
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I folded up some thin brass sheet for the amplifier/ filter I’m currently using. A nice milled case looks great but I don’t think 5mm of Aluminium will make it much better
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the 5mm aluminium mounted flat underneath the PCB might be doing a better job at heatsinking than your (admittedly beautifully made) brass origami
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I really do want a CNC milling machine! But... was just thinking that it would be a good exercise in filing and fitting to make an aluminium enclosure with hand tools
With the Gali 84+ most heat seems to be dissipated in the resistors setting the 100mA bias current when it is run from a 13V supply. As I intend to fit it in the case with my Spectrian amplifier I will install a 9V regulator so the bias resistors can be adjusted accordingly and make it run cooler.
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The same amount of heat dissipated, just in a different place. It might be easier just to use a larger dropper resistor rather that a regulator as the current is constant
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Mike that's absolutely fair comment, it's just a lack real estate on the SV1AFN pcb. So in this case it will be a regulator soldered to the brass origami which will also compensate for supply variations.
The thing that's griping me a bit presently is the number of operators I see showing systems using Lime / Pluto / HackRF as prime movers with broadband "Far East" amplification and no stage filtering i.e. Lime / Pluto-> Broadband amp -> WiFi Amp. Which pretty much relies on the antenna as the system filter. Ok it's heading out to space but..! Am I being a bit old fashioned?!
I'm learning KiCad so hope to be able to add something to the community in due course.
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Yes and it works fine. You will though need an oven or hot air to build it.
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Hi Clive
this is exactly my problem ...
@forum Anyone a spare pre-build one for me?
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What do you guys use for output LP filter?
Lumped, stripline, pipecap? -
None ... well ... the TX-antenna is a BPF : -) (you transmit towards the sky ... )
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What do you guys use for output LP filter?
Lumped, stripline, pipecap?73 de Frank
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some words here on the TQP7M9103. I got my driver board today, which claimed 16dB Gain and 29dBm P1dB. From the datasheet, it was obvious that this cannot be given over the full frequency range as the Qorvo device needs a bit of matching at the input and output.
First measurements: 6dB gain and ca. 20 dBm P1dB. I suspect therefore that this could be improved with some snowflaking (Faehnchenschieben) and as this is low enough power to be safe, I'll go for it
The output inductance (L1) for the bias supply also seemed a bit large to me (too low SRF) so I exchanged it to a part with known parameters (22nH, 0603, 4.6GHz SRF) but this improved matters only little. Will try some snowflaking over the weekend.
Hello Achim,
do you have new conclusions about that device?
73, Mike
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.. and you can easily build one on your own:
http://www.vk3um.com/interdigital%20filter.html
vy73 DB8TF
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.. and you can easily build one on your own:
http://www.vk3um.com/interdigital%20filter.html
vy73 DB8TF
DB8TF kann er nicht weil ich keine Mechanikwerkstatt mein Eigen nenne. Reicht wenn ich genug Messtechnik für den elektronischen Kram habe.
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Looking at the original photo #1 on this thread, it looks like there is a lot going on between the output of the device and the SMA connector. On the data sheet it suggests that at 2.4G there should be only a 1.5pF capacitor to ground. Personally I would disconnect all those components and just AC couple the output to the SMA.
Here I've just received some Qorvo RFPA5208 ICs from Mouser. Now I need to design the board for the rest of a low cost upconverter.
The RF should be fine....but setting the frequency of the ADF4351 with a PIC sounds like hours of frustration. Can a PICStart+ program a 12F629 ?? -
but setting the frequency of the ADF4351 with a PIC sounds like hours of frustration. Can a PICStart+ program a 12F629 ??
If you are familiar with Arduino you might want to use that to program the ADF4351 instead of using a PIC.
Arduino code and electrical schema here:
https://github.com/HarrydeBug/…GHz-Frequency-Synthesizer -
The RF should be fine....but setting the frequency of the ADF4351 with a PIC sounds like hours of frustration
Hi David,
ther is no frustration with. Use a ATTINY13 programmed with Arduino software or i can do this for you.
Look at this https://www.hamshop.cz/pll-adf…d-with-attiny13-kit-i351/
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Great! Thank you for sharing.
I have a module I have not built yet so nice to get some outside validation that it works well.
I will use a 1.6mm PCB and manually cut 50ohm stripline with a scalpel to my SMA edge connectors as the module seems to be made to have a 1.6mm PCB between its pins and the ground-plate.
How much heat is it generating for you?I guess your big heat-sink is little bit overkill at 0.4W ?
//Harry
