I have been playing with a new Triquint ULNA device (TQP3M9036). It
Shows a lot of promise. It is like a MAR or MSA device in that it is
50ohm in and out. and has a claimed NF about .4db nf ( their numbers).
I have built several pramps to test them and have gotten even better
than they claim and they cover 50-1296 with ease and NF is .4ish or
below. The S11 and S22 are both great and the OIP3 is +35db also
...very nice device. It has great promise as a good terrestrial LNA.
Preamps are foolproof to build and would cost under $50 if all the best
quality parts are used.
Just for information only ...
The information in this email may be confidential and/or privileged. This email is intended to be reviewed by only the individual or organization named above. If you are not the intended recipient or an authorized representative of the intended recipient, you are hereby notified that any review, dissemination or copying of this email and its attachments, if any, or the information contained herein is prohibited. If you have received this email in error, please immediately notify the sender by return email and delete this email from your system.
I have been toying with the idea of getting a station on EME for close to
15 years now, so I figure it's time to get going.
>From my home QTH in JO59BR, I should be able to work the moon when it's
between 150 degrees and 280 degrees, so for a fair bit of each month. Going
further north there are a lot of trees in between and a hill.
I have been collecting parts for some time in order to do a station setup,
although I'm unsure if I should plan on starting on 70cm or 23cm. I
believe 23cm has more stations than 23cm?
2M is probably not viable from where I'm living, neither is a dish antenna
for higher frequencies.
My planned station setup will be:
Flex 6600 or Elecraft K3 locked to GPSDO
Transverter (I have homebrew for 70cm, and DB6NT G2 for 23cm)
Power amplifier (Either 300W on 70cm or a 600W W6PQL brick on 23cm is
WIMO yagi ( either 8M 20dBi on 70cm or 5M 22dBi on 23cm)
I'm quite unsure with regard to pre-amps. I know there are some nice sub
1dB NF preamps around, and I guess that makes sense since I will be limited
in gain with a single yagi?
Coax relays, switching and such should not be the hardest thing to get
going, I have a well filled junkbox with such parts. For antenna rotation,
I have a couple rotors so I should be able to do a setup that tracks the
moon fairly well. without too much effort.
Does this sound like a reasonable approach? I would like to be able to do
CW and digi QSOs with a limited station to start with. Are there any
obvious pitfalls I should be aware of?
73 de Thomas LA3PNA.
With Best regards, Thomas S. Knutsen.
Please avoid sending me Word or PowerPoint attachments.
I will try to! But is difficult to go to the bottom....
Talking about 432 MHZ EME Losses before the preamp are important.
So normally direct at the antenna there is a coaxrelay with high
isolation between te TX and RX port (80dB or so). Preamp is mounted
directly at the antenna and screwed to the relay to prevent losses. I
always used seperate feedlines for RX and TX.
So the coaxrelay provides the isolation. Normally no relays inside the
preamp are used. In Europe the EME HF400 relay is popular with EME-ers.
I am not so familar with the USA relays but Transco is a name often
heard but there will be others for sure!
Preamp & power amp are switched with a decent sequencer and the power
comes via a separate cable, others use the coax.
Have a play with the VK3UM EME calc software, will be a steep learning
curve but will give you a good idea.
Or this article:
I hope this helps...
73 Geert PA3CSG
Op 30-06-2022 om 18:10 schreef wemccourt:
> Do these preamps have rf sensing protection, a 12 volt dc power
> requirement and are they suitable for outdoors mounting say on antenna
> mast or tower leg?
> I'm new to this facet of the hobby and just learning my way forward.
> Thank you for answering what are, to you, aw probably foolish questions.
> Bill WF1L
> Dover DE
> Sent from my Verizon, Samsung Galaxy smartphone
> -------- Original message --------
> From: Geert PA3CSG via Moon-net <moon-net(a)mailman.pe1itr.com>
> Date: 6/30/22 11:03 (GMT-05:00)
> To: moon-net(a)mailman.pe1itr.com
> Subject: [Moon-Net] For sale
> I have for sale 2 preamps for 432 MHz with MGF1302 DJ9BV design in a
> silverplated box.
> Noise figure around 0,3dB gain single stage about 19dB
> Input is a N type male output is a N type female connector
> €35 each plus shipping
> Please contact of list.
> 73 Geert PA3CSG
> Moon-Net posting and subscription instructions are at
I have for sale 2 preamps for 432 MHz with MGF1302 DJ9BV design in a
Noise figure around 0,3dB gain single stage about 19dB
Input is a N type male output is a N type female connector
€35 each plus shipping
Please contact of list.
73 Geert PA3CSG
I posted a question about how to Doppler track in MAP65 when using the FunCube Pro + dongle. The standard way appears to be to use something like HDSDR or SDR Console to control the FunCube Pro+. You then stablish a CAT control link between WSJTX and a Rig Emulator (TS2000) which is built into the SDR program, using a virtual com port. You then have to configure the SDR program to out put an I/Q stream to WSJTX via a virtual audio channel. Probably doable if you can get the virtual ports configured correctly and find all the settings hidden in the SDR program!
But there is a simpler way. WSJTX has a Hamlib RIG entry for the Funcube pro+. That enables direct CAT control of the FunCube frequency from WSJTX itself without needing and external SDR program. But that's all it does. It doesn't help WSJTX to understand an I/Q audio stream. At the same time with the same FunCube pluged into the same PC, you can configure MAP65 to read the I/Q audio stream from the funcube. So WSJTX is controling the funcude frequency and MAP65 is reading the I/Q output and decoding the signal.
You might ask "why not just decode the message using WSJTX" and the answer is that it does not understand the I/Q stream from the FunCube. It interprets it as regular SSB audio, but it isn't. Without demodulation, the I/Q stream appears as a DSB signal with both upper and lower sidebands, so it has full image response. That means if it tunes to a signal, it's also seeing whatever is on the image frequency, which will typically be just noise (and that's the best case!). So you see twice the noise you would for an SSB signal and hence end up with a 3dB worse SNR. If there's a signal on the image frequency, as well as noise, you probably won't get a decode at all.
The crucial points are this is that WSJTX can Doppler track, understands regular SSB audio, but not an I/Q audio stream, while MAP65 can't Doppler track, understands an I/Q audio stream, but not regular SSB audio. Working together you can build a system that can Doppler track and can understand I/Q audio.
I've more or less documented this at https://bobatkins.com/radio/funcube.html
Thanks for all the tips and suggestions.
I have a Kuhne G5 3cm transverter which I am using with a 432MHz IF.
I am of course aware of Kuhne Suite, but can find very little useful
documentation about using it.
I'd appreciate advice about receiving JA stations at 10,450MHz.
Obviously, the LO needs to change between Tx and Rx, but haw best to achieve
that? And any issues with Doppler tracking with WSJT-X?