实践是检验真理的唯一标准
The copper looks like a capacitor, maybe showing more inductance...For lack of standard measuring equipment and more theoretical knowledge support, practice is the best method.I like that, maybe one day there will be an opportunity to have a measure or a theoretical analysis of the results.You will say.Oh, I see.
Hi Achim,
thanks for the hint. SDR-Console supports an USB-Relay meanwhile, so switching the supply is simple but not very elegant. The LimeSDR Mini gives approx. 0 dBm, the total current to the amp. is about 2 Amps.
At present, I use all the equipment in a portable way, the dissipation is limited. But for longer standby a switch off of the idle current is useful. The picture shows the "Radio" below the laptop.73s
Andreas, DL5CN
Beautiful design.Does the limesdr mini work properly on the usb hub?
Hi OMs,
because nearly every day a couple of emails arrive here about the modification of the small Andrew MRF21045 amplifier i digged mine out of the pile of "old" amplifiers and took some pictures.
vy73 DB8TF
What is the purpose of adding copper sheet?How does the dimension of copper sheet work out?I am curious and want to learn this reason.The pa design work I used is between 1900 and 2100. I also need such modification.
https://github.com/ok1cdj/ADF4351-basic-LO
Here are all the references.Circuit and program based on ok1cdj
@DO1CTI
[附= 1257] [/附加]
My qo-100 up/down converter is complete.
GPSDO provides a 10M reference signal.The experimental test works well, but it has not been used in practice.
Thanks to PA3FYM for your help.
To find your location on Google earth, draw a line with a ruler and drag the endpoint.You can get the Angle relative to the starting point.If the Angle is true north, it is very accurate...
I'm interested in how you did it.
Tell me what you think.I'll check the PDF carefully to see if it has anything to do with it.
Maybe an umbrella is more portable
I found two cavity filters, the original parameters: 2400-2500. I adjusted them.The larger white final insertion loss is small - about 1db.The black one is about -2db
Now we can be sure that the signal is not strong enough... Maybe I need a 3M antenna to receive the WB TV signal, now I use 1.2m
I tried to receive WB beacon again today, but still failed. My position antenna elevation Angle is 18 degrees.S/N MER is 1-2 at its highest. I really missed it.But you can have a pleasant QSO in NB mode.The uplink WB mode was tested.The 250k code rate can be seen on websd-wb that my signal is only 2-3db.
I did some pipe cap filter...:)
Yesterday I "umbrella" the RX antenna test.Aim at the satellite, NB signal 20 db higher than noise.WB clearly did not see any bumps on the spectrum.I am the right way to set the polarization.But I still didn't receive the WB eshail2 with minitioune beacon.I really miss...
Who can give me a minitioune. Ini configuration file?
I built a building blocks:)
Use an rf switch to switch the RX/TX. AT13 control,UV2 just in order to facilitate testing.I will use FT991A.
rx_out
tx_out
There is currently no join any filter.But I think the filter is indispensable
All the things here.Bring many convenient module.Let me set up quickly
I reorganize the intermediate frequency.To calculate the LO.I don't know whether this is appropriate.
In 10489.55 as an example.RX - LNB = 739.55.LO = 300. IF = 739.55-300 = 439.55, TX = 2400.05, LO = 1960.5. IF = 1960.5 + 439.55 = 2400.05.
I almost put together the required modules, but did not know how to mix of RX/TX IF I FT991A. Lo switch signals FT991A have PPT can give T13A the IO of the microprocessor to control the lo frequency switch
As for duplex mode, I can put a computer after the SDR beside, this is not a problem
PA3FYM I am following your footsteps. Today I got ADF4351 and programmed the register with t13a, which can output the desired signal.But I think a filter is necessary.How can I design a filter that requires frequency?
Thank you for your prompt, I tried to set LO when test last weekend.But the position of the decimal point.
