Date   
I'm I likely to hear anything off the moon? Newbie question

Nick Gregory G0HIK
 

Am I kidding myself or am I likely to hear anyone off the moon on 23cm's ?

Dual Antennas 70 ele
SG-Labs LNA, quoted as 0.8dB
IC-9700

I have just measured the sun noise at around 2 to 2.5 dB compared to the cold sky, the SFU is l think low today at 67.

I need to do some more reading and use the VK3UM software, but this is sort of all done portable so one step at a time.

Thanks

Nick

Re: I'm I likely to hear anything off the moon? Newbie question

SAM JEWELL
 

Nick,
Point at the moon when the elevation of the moon is above 10 degrees (actually in Belgium, but therefore close for the UK). You should be able to detect the ON0EME  beacon on 1296.000MHz. Remember, due to doppler, it will be up to 2kHz above that on moonrise, although the beacon won’t yet be on at that elevation!) and 2kHz low at moonset (it will have set in Belgium and therefore have been off for around an hour).
The beacon will be weak on that setup you describe, but you should hear it and certainly see it on Spectran or similar.
Run WSJT (not X) on JT65C and you will get a measure of the beacon level. I expect you will see around -20 —22dBJT, even though it is not running JT modes.

73 de Sam, G4DDK

On Wednesday, June 19, 2019, 12:25 pm, Nick Gregory via Groups.Io <nickg0hik@...> wrote:

Am I kidding myself or am I likely to hear anyone off the moon on 23cm's ?

Dual Antennas 70 ele
SG-Labs LNA, quoted as 0.8dB
IC-9700

I have just measured the sun noise at around 2 to 2.5 dB compared to the cold sky, the SFU is l think low today at 67.

I need to do some more reading and use the VK3UM software, but this is sort of all done portable so one step at a time.

Thanks

Nick

Re: I'm I likely to hear anything off the moon? Newbie question

Nick Gregory G0HIK
 

Thanks Sam,

That is encouraging, trying for ON0EME was one of my next steps. I was thinking I would not hear it as see the station is not  particularly large.

I'll get the software loaded up and give that a try.

Does 2 to 2.5dB sun noise sound about right ?

Nick G0HIK

Updated SignalNoiseMon software

Andy G4JNT
 

Anyone wanting to measure S/N of received signals accurately including off the Moon, (as Sam's reply to Nick  just now mentioned)
The latest update to my Signal  /  Noise monitoring prog is here.  


It cures a potential lockup situation at startup if you've stored invalid settings .
I've also added an input squaring option to regenerate a carrier from certain types of modulation like BPSK.   Got the idea from that seeing that Simon Brown's SDR Console uses the BPSK beacon for frequency locking.    It's there mainly for frequency tracking QO100 -  better than trying to use the CW beacon.

Other soundcard DSP stuff can be found here   http://g4jnt.com/dspsw.htm 
 


Re: I'm I likely to hear anything off the moon? Newbie question

SAM JEWELL
 

Nick,
Yes, a little low, but not unacceptable with the yagis, that LNA noise figure and the current SFI.
A VERY useful test is to switch the LNA on and off. AGC should be disabled (easy on the 9700). The level of noise should go up by at least 10dB when the LNA is on. It should be terminated in 50R for this test. A noise rise of around 15dB would be better.
The noise figure of the IC9700, on 23cm, is around 4.8dB measured on mine (internal preamp on). Use AppCad to determine what noise increase you should get. Also, be aware, when the LNA is off it may have a significantly different impedance to when on and this may affect the IC9700 noise output, so a few dB difference from what Appcad says is not unrealistic.
Let us know what numbers you get.

73 de Sam, G4DDK

On Wednesday, June 19, 2019, 12:50 pm, Nick Gregory via Groups.Io <nickg0hik@...> wrote:

Thanks Sam,

That is encouraging, trying for ON0EME was one of my next steps. I was thinking I would not hear it as see the station is not  particularly large.

I'll get the software loaded up and give that a try.

Does 2 to 2.5dB sun noise sound about right ?

Nick G0HIK

Re: Updated SignalNoiseMon software

SAM JEWELL
 

Thanks Andy.

Any thoughts about my posting about using a version of the beacon locking facility to lock an LNB to a ‘pseudo’ beacon down in the narrowband 10368MHz region? Maybe generating a ‘beacon look alike’ to run locally (like at home’ to lock the LNB a la SDR Console’ for QO100?

Sam

On Wednesday, June 19, 2019, 12:56 pm, Andy G4JNT <andy.g4jnt@...> wrote:

Anyone wanting to measure S/N of received signals accurately including off the Moon, (as Sam's reply to Nick  just now mentioned)
The latest update to my Signal  /  Noise monitoring prog is here.  


It cures a potential lockup situation at startup if you've stored invalid settings .
I've also added an input squaring option to regenerate a carrier from certain types of modulation like BPSK.   Got the idea from that seeing that Simon Brown's SDR Console uses the BPSK beacon for frequency locking.    It's there mainly for frequency tracking QO100 -  better than trying to use the CW beacon.

Other soundcard DSP stuff can be found here   http://g4jnt.com/dspsw.htm 
 


Re: I'm I likely to hear anything off the moon? Newbie question

Nick Gregory G0HIK
 

Thanks again Sam,

I'll do some more tests then, when I can get the kit setup up again and will report back.

Nick G0HIK

Re: Updated SignalNoiseMon software

Andy G4JNT
 

Hmmm.

I did do something like that using a Fract-N synth LO (prompted by a G0API requiremnt)- you may remember a demo I did of it at, I think,  RAL, a goodly few years ago.
But was a bit clunky and once people had started locking their LNBs, was  best forgotten

It's the frequency control that is the difficult bit.  Unless integrated into a complete SDR suite there has to be some mechanism in place to tune real hardware in real time.   I'm not in the writing SDR software league - and Simon has done it anyway.   What could be done, is to generate a BPSK beacon and use Simon's existing software, fooled into operation at a lower frequency.  But I suspect his locking is tied specifically to QO100 and LNBs so doubt that would be easy, without getting him to modify his code.   And if he's going to do that, why not just request what you actually want added to SDR Console. Like locking to a carrier at some frequency you specify.

But if that isn't possible:
First try to set SDR console to 618MHz  and see if it lets you use the locking facility. 
If so then try generating a simple BPSK signal at 10368.8 - a synth hitting a DBM at some odd order subharmonic, then hit the IF port with a square wave at 300Hz.   Or start off trying it at the QO100 frequency in the first place.   For all I know (I don't use SDR Console here) it may work with a carrier anyway.

Going back to my original solution, could be done via CAT if you are converting LNB output down to some frequency a transceiver can tune, but what protocol?  Hamlib for general CAT control is a nightmare and I won't touch it.  So a custom job for the FDM DUO (TS-480) from here and that's it !!!

 


On Wed, 19 Jun 2019 at 13:02, SAM JEWELL via Groups.Io <jewell=btinternet.com@groups.io> wrote:
Thanks Andy.

Any thoughts about my posting about using a version of the beacon locking facility to lock an LNB to a ‘pseudo’ beacon down in the narrowband 10368MHz region? Maybe generating a ‘beacon look alike’ to run locally (like at home’ to lock the LNB a la SDR Console’ for QO100?

Sam



Sent from Yahoo Mail for iPad

On Wednesday, June 19, 2019, 12:56 pm, Andy G4JNT <andy.g4jnt@...> wrote:

Anyone wanting to measure S/N of received signals accurately including off the Moon, (as Sam's reply to Nick  just now mentioned)
The latest update to my Signal  /  Noise monitoring prog is here.  


It cures a potential lockup situation at startup if you've stored invalid settings .
I've also added an input squaring option to regenerate a carrier from certain types of modulation like BPSK.   Got the idea from that seeing that Simon Brown's SDR Console uses the BPSK beacon for frequency locking.    It's there mainly for frequency tracking QO100 -  better than trying to use the CW beacon.

Other soundcard DSP stuff can be found here   http://g4jnt.com/dspsw.htm 
 


Re: I'm I likely to hear anything off the moon? Newbie question

SAM JEWELL
 

Thanks Andy,
I did think just a synth harmonic and  simple BPSK modulator. Maybe GVA123 amplifier.....
I don’t think that the RSP2 has anywhere enough bandwidth to lock to the 10486.800MHz beacon and tune at 618MHz. Anyway, you would be beaming at vastly different headings for terrestrial monitors of beacons etc,
I never thought to try checking lock to a carrier only. The pseudo beacon looks easy enough.

Sam

On Wednesday, June 19, 2019, 1:17 pm, Nick Gregory via Groups.Io <nickg0hik@...> wrote:

Thanks again Sam,

I'll do some more tests then, when I can get the kit setup up again and will report back.

Nick G0HIK

Hello

Oguzhan Kayhan
 



Although I am not a UK station, I am deeply interested in ghz bands. Sadly nobody around my zone interested on this part of the band.

That's why I joined your mail list to follow the conversations and to get some knowledge, catch some tricks to be QRV on this magical bands..
 

I might ask some silly questions sometimes.. Please excuse me for this.

Best Regards , 73


TA2NC
Oguz

Re: Activity List for the UK Microwave Group mm-wave contests - Sunday 23rd June 0900-1700z

Barry Lewis
 

John,
If the weather is looking reasonable I expect to pitch up on Walbury Hill on Sunday to operate the 24GHz UKuG loan gear. Operation from around 10:30.
Talkback on KST and maybe 2m.
73
Barry
G4SJH

Re: Hello

Dave - G4RQI
 

Welcome to the group Oguz

73 David - G4RQI


From: UKMicrowaves@groups.io <UKMicrowaves@groups.io> on behalf of Oguzhan Kayhan <oguzhan@...>
Sent: Wednesday, June 19, 2019 1:58:32 PM
To: UKMicrowaves@groups.io
Subject: [UKMicrowaves] Hello
 


Although I am not a UK station, I am deeply interested in ghz bands. Sadly nobody around my zone interested on this part of the band.

That's why I joined your mail list to follow the conversations and to get some knowledge, catch some tricks to be QRV on this magical bands..
 

I might ask some silly questions sometimes.. Please excuse me for this.

Best Regards , 73


TA2NC
Oguz

Re: Hello

Richard <richard@...>
 

Hi Oguz
I just looked up your QTH and it is not the ideal microwave location, and far inland for QSOs from where there is some microwave activity to your NW and west.
Your ideal solution may well be to look at getting going of the repeater in the sky QO-100.
For you the dish elevation is high and it would give you the opportunity to play with 10GHz for the downlink and 2.4 GHz for the uplink.
Last time I drove past your qth I noticed plenty of medium sized mesh dishes around 1.8mtr diameter, so if you managed to use one of those the amount of power needed on 2.4 GHz would be low.

HTH ,73 Richard g8JVM


On Wed, 2019-06-19 at 15:58 +0300, Oguzhan Kayhan wrote:


Although I am not a UK station, I am deeply interested in ghz bands. Sadly nobody around my zone interested on this part of the band.

That's why I joined your mail list to follow the conversations and to get some knowledge, catch some tricks to be QRV on this magical bands..
 

I might ask some silly questions sometimes.. Please excuse me for this.

Best Regards , 73


TA2NC
Oguz

-- 
 Best wishes /73 
 Richard Bown
 
 Email : richard@...

 HTTP  :  http://www.g8jvm.com
 
 ######################################################################

 Ham Call: G8JVM . QRV: 50-432 MHz + Microwave 
 Maidenhead QRA: IO82SP38, LAT. 52 39.720' N LONG. 2 28.171 W
 QRV 6mtrs 200W, 4mtrs 150W, 2mtrs 300W, 70cms 200W, 
Microwave 1296MHz 140W, 2320MHz 100W & 10368MHz 5W
 OS: Linux Mint 19.1 x86_64 Tessa, on a Dell Inspiron N5030 laptop
 ######################################################################

Re: Offset dishes for repeaters in the sky

John Lambo
 

Nice work again Neil !!!!


73  John  PA7JB


Op 19-6-2019 om 11:29 schreef Neil Smith G4DBN:

On 19/06/2019 09:44, Colin G4EML wrote:
Fitting the dual band patch to a standard feed arm can lead to it being positioned too close to the dish. This is because most feed arms are designed for a standard LNB with a horn diameter of about 60 mm. The reflector of the patch feed is larger, forcing it to be positioned closer to the dish to avoid fouling on the feed arm. For correct positioning at the focal point it is necessary to modify the end of the arm to give more clearance. 

Here's one I made earlier, as Valerie Singleton might have said...

The block at the right side plugs into the sawn-off end of the feed arm and gives a bit more clearance, while still allowing the feed to be on the right axis and at the right focal distance.

However, in some cases, it is adequate to use a split adaptor ring with a 22mm offset hole and 40mm OD and nod the dish by a degree or so. That gains around 8mm of extra clearance. Something like this, but with the hole nearer the periphery:

I went a bit mad on the adjustability front with an earlier version for a WA6KBL Pickett-Potter horn which fits in the cut-off end of the arm on my 95cm dish.

Neil G4DBN



Re: I'm I likely to hear anything off the moon? Newbie question

Nick Gregory G0HIK
 

It's a little bit strange.

With the AGC off, the 9700 Pre-amp on and the LNA terminated into 50R, I am getting a ON/OFF change of 7dB.

Any ideas why it is so low.

Measured using a A.C. millivoltmeter.

Nick G0HIK

Re: I'm I likely to hear anything off the moon? Newbie question

SAM JEWELL
 

LNA gain too low? Cable loss too high? IC9700 noise figure a bit higher? What does Appcad say for the parameters you have? 
This should be easy to determine. My guess is low LNA gain,  but what cable and length do you have between the LNA and 9700?
Sam





On Wednesday, June 19, 2019, 8:37 pm, Nick Gregory via Groups.Io <nickg0hik@...> wrote:

It's a little bit strange.

With the AGC off, the 9700 Pre-amp on and the LNA terminated into 50R, I am getting a ON/OFF change of 7dB.

Any ideas why it is so low.

Measured using a A.C. millivoltmeter.

Nick G0HIK

Re: I'm I likely to hear anything off the moon? Newbie question

Nick Gregory G0HIK
 

The cable is 2mtrs of RG223, about 1dB loss including connectors.

LMR400 would improve this to around 0.5dB including connectors, I dont know if SMA's are available for LMR400, if not having an adapter is going to bring the loss up to 1dB again I would think.

I've never used Appcad, I'll have to load it up and learn it when I get time.

Nick
 

Re: I'm I likely to hear anything off the moon? Newbie question

SAM JEWELL
 

Not cable loss.
What is the gain of the LNA?
Is the LNA really close to the yagi feedpoint? How much cable and type?


Sam

On Wednesday, June 19, 2019, 10:11 pm, Nick Gregory via Groups.Io <nickg0hik@...> wrote:

The cable is 2mtrs of RG223, about 1dB loss including connectors.

LMR400 would improve this to around 0.5dB including connectors, I dont know if SMA's are available for LMR400, if not having an adapter is going to bring the loss up to 1dB again I would think.

I've never used Appcad, I'll have to load it up and learn it when I get time.

Nick
 

Re: I'm I likely to hear anything off the moon? Newbie question

SAM JEWELL
 

Yes, SMAs are available for LMR 400. I just bought some from Superbat on line (Chinese company, of course).

Sam

On Wednesday, June 19, 2019, 10:11 pm, Nick Gregory via Groups.Io <nickg0hik@...> wrote:

The cable is 2mtrs of RG223, about 1dB loss including connectors.

LMR400 would improve this to around 0.5dB including connectors, I dont know if SMA's are available for LMR400, if not having an adapter is going to bring the loss up to 1dB again I would think.

I've never used Appcad, I'll have to load it up and learn it when I get time.

Nick
 

Re: I'm I likely to hear anything off the moon? Newbie question

Nick Gregory G0HIK
 

Sorry I've just reread you message, I've got approx 8 mtrs of RG223 after the pre-amp, which is around 4db, I thought that loss after the pre-amp was not as important as before.
The reason for the 5mm cable is the whole station can be made carryable to fell tops, but I can easily change to something better, for which SMA's are available for.

Nick