Hi Jerry.
That looks good. A little sealent will keep the water out.
I like the 25mm antenna element clamp. I'm sure there are a few of those in the 'spares box'. Thanks for the ideas
73 David
Hi Jerry.
That looks good. A little sealent will keep the water out.
I like the 25mm antenna element clamp. I'm sure there are a few of those in the 'spares box'. Thanks for the ideas
73 David
I've got my SG-Labs transverter and it's working well. With 2 Watt + 1dB RG142 cable loss I'm a bit above the CW-beacon level. I use it with GPSDO.
"Door open".
The LNB is modified and has now an external LO (GPSDO from Leo Bodnar), see here: Twin LNB HD-BP2 with external LO.
My GPSDO settings: 27 MHz & 10 MHz
Link to a Triplexer.
On 432MHz I use as exciter a FT-100 or an old analog IC402 from the 70ties (no PLL, no TCXO and drifting a bit ).
My NB setup is complete so far.
Just a note: triplexer = diplexer + DC.
Update!
Now I know the type of my old dish and some technical data:
Hirschmann - CSA 1212 G
Polarmount - CPM 1200 B
Feedmount - CDB 1200 G
Diameter d = 1,20m
f = 11.325 GHz
noise temperature @ 30° el. = 30 K
G/T (with 1.5dB NF of LNB)
gain = 40.6 dBi
beamwitdh (-3 dB) <= 1.5°
weight = 29.8 kg
wind load = 1.3 kN (@800 N/m^2, c =1.2)
pardon the question, but why do the two measurements differ so vastly? It is certainly fine for 2.4g but I don't understand the rest of the behaviour. Do you have pictures of the two setups?
pardon the question, but why do the two measurements differ so vastly? It is certainly fine for 2.4g but I don't understand the rest of the behaviour. Do you have pictures of the two setups?
Achim, my suspicion is that the adapter "MACOM N-male-SMA-female" not present in the circuit during the calibration phase has distorted the measurements.
Mike, DL1GNM will be able to clarify the matter better.
DD0KP yes, the 10G lens has no effect (shouldn't). I8LYL former I0LYL I suspect either the adapter to be wonky or the way the N/SMA connectors were fixed to the reflector. It's just out of curiosity, the return loss and 'twist' at 2.4g looks fine to me.
Just moved around the Smith chart due to the different line length I think.
Ah, that explains it and is actually very reasonable. Thanks for the solution!
Mike is right.
This is unusual.
Meanwhile I've modified several LNBs for external LO feed. Therefore I use the NB output to supply the LNB with 25MHz, DC and of course the downlink.
Using my 27 MHz HD-Line HD-BP2 gives me still a DATV Beacon MER of 10.7dB.
The following LNB are not as good as the HD-BP2, I loose about 1dB (!) sensitivity:
OCTAGON Twin Green HQ, Model: OTLG GreenHQ, no Serial No. T1015, SPT SP4202HN, 25 MHz X-Tal,
like OE2ROL did: https://www.oe2rol.com/octagon-lnb-umbau-fuer-qo-100.html
OPTICUM TWIN LTP-04H
Same as AMSAT shows here: OPTICUM LTP 04H Twin LNB
In all cases the Leo Bodnar GPSDO was used. I tried to optimise the LO Power, but still no improvement compared to my old LNB.
To Try: Diavolo Twin. Transformer missing. See here: https://elektronik-muenster.de…lnb-f%C3%BCr-externen-lo/
I want to change, because my own GPSDO will have 10 MHz + 25 MHz.
Any suggestions? Please let me know. Thank you.