Date   

Re: NDB - Airspy HF+ DIscovery versus Hermes Lite 2

Allan Isaacs
 

They’re easy enough to come by Tom.

This one belongs to the son of silent key G3PNV and has lain dormant for the best part of 50 years.

https://www.radiomuseum.co.uk/modR1155.html

Sacriligiously the dial is now a Muirhead but even smoother than the old type 35.

My first was bought from my English teacher for £3 (quite a lot of cash in those days when a good wage was £1 a day and suffice to say my parents hit the roof). Since then I acquired a few more with one coupled to a T1154.

All the best

Allan G3PIY

 


From: main@SDR-Radio.groups.io [mailto:main@SDR-Radio.groups.io] On Behalf Of Tom Crosbie G6PZZ
Sent: 23 December 2021 14:58
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] NDB - Airspy HF+ DIscovery versus Hermes Lite 2

 

You lucky man Allan!

I almost had one around 1970. It sat at the back of the physics lab and someone had removed all the valves. Couldn’t afford them on pocket money. Never thought of hanging on to it until I started work and could afford it.

That tuning dial was really smooth.

 

Season’s greetings

 

Tom G6PZZ

 


Re: NDB - Airspy HF+ DIscovery versus Hermes Lite 2

Alan G4ZFQ
 

Unless I have a sub-par HF+? Wonder if you managed to watch my video recordings of the NDB?
Max,

I did. It seems the Airspy is excessively noisy. Levels appear to be high. I can not believe that a good Airspy could be that much worse.

What antenna? It could be that some out of band signal is causing the problem. Sometimes I use a LPF but that's not normally needed unless I TX.

73 Alan G4ZFQ


Re: NDB - Airspy HF+ DIscovery versus Hermes Lite 2

jdow
 

You have a really small antenna, perhaps? If not I suspect the Andrus is not setup as nicely as it could be. With a low loss antenna system below even 30 MHz and especially under 10 MHz it is VERY difficult to make a radio too insensitive to receive anything that is out there without reducing RF input gain by 10 dB to even 30 dB due to purely natural noise sources.

{o.o}

On 20211223 06:46:56, Allan Isaacs wrote:

Max.. I’m overhauling a WW2 R1155 and as I tuned across the long wave band a Polish station close to Radio 4 came in at a good S8 about mid day.

I checked on my Andrus SDR with the same aerial and it wasn’t more than a tiny spike with no audible modulation

Admittedly the R1155 has been modified with a 6AK5 RF stage…

Allan G3PIY


From: main@SDR-Radio.groups.io [mailto:main@SDR-Radio.groups.io] On Behalf Of Max
Sent: 23 December 2021 14:36
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] NDB - Airspy HF+ DIscovery versus Hermes Lite 2

 

On Thu, Dec 23, 2021 at 12:34 PM, Patrick wrote:

It's indeed surprising.

As a LF enthusiast (chasing NDB for more than 20 years), I can tell the Discovery is one of the most sensitive receiver I have ever used

Hi Patrick

I don't think this shows any issue with the HF+ Discovery, just that the Hermes Lite 2 is a quite astonishing bit of kit for the money. Actually regardless of the cost. Punches way above its weight. I did always think so but this has just confirmed it for me. Unless I have a sub-par HF+? Wonder if you managed to watch my video recordings of the NDB?

Unfortunately I was not able to listen for Grimeton test transmissions today. Listening now but nothing heard so I guess too late to the game. I will be sure not to miss the main TX tomorrow morning.

Max



Re: NDB - Airspy HF+ DIscovery versus Hermes Lite 2

Tom Crosbie G6PZZ
 

You lucky man Allan!

I almost had one around 1970. It sat at the back of the physics lab and someone had removed all the valves. Couldn’t afford them on pocket money. Never thought of hanging on to it until I started work and could afford it.

That tuning dial was really smooth.

 

Season’s greetings

 

Tom G6PZZ

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Allan Isaacs
Sent: 23 December 2021 14:47
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] NDB - Airspy HF+ DIscovery versus Hermes Lite 2

 

Max.. I’m overhauling a WW2 R1155 and as I tuned across the long wave band a Polish station close to Radio 4 came in at a good S8 about mid day.

I checked on my Andrus SDR with the same aerial and it wasn’t more than a tiny spike with no audible modulation

Admittedly the R1155 has been modified with a 6AK5 RF stage…

Allan G3PIY


From: main@SDR-Radio.groups.io [mailto:main@SDR-Radio.groups.io] On Behalf Of Max
Sent: 23 December 2021 14:36
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] NDB - Airspy HF+ DIscovery versus Hermes Lite 2

 

On Thu, Dec 23, 2021 at 12:34 PM, Patrick wrote:

It's indeed surprising.

As a LF enthusiast (chasing NDB for more than 20 years), I can tell the Discovery is one of the most sensitive receiver I have ever used

Hi Patrick

I don't think this shows any issue with the HF+ Discovery, just that the Hermes Lite 2 is a quite astonishing bit of kit for the money. Actually regardless of the cost. Punches way above its weight. I did always think so but this has just confirmed it for me. Unless I have a sub-par HF+? Wonder if you managed to watch my video recordings of the NDB?

Unfortunately I was not able to listen for Grimeton test transmissions today. Listening now but nothing heard so I guess too late to the game. I will be sure not to miss the main TX tomorrow morning.

Max


Re: NDB - Airspy HF+ DIscovery versus Hermes Lite 2

jdow
 

One other thing - if he is not using the AirSpy HF+ Discovery's AGC he's very likely running with some gain mismatches in the analog portion of the chain.

{^_^}

On 20211223 06:36:19, Max wrote:
On Thu, Dec 23, 2021 at 12:34 PM, Patrick wrote:
It's indeed surprising.
As a LF enthusiast (chasing NDB for more than 20 years), I can tell the Discovery is one of the most sensitive receiver I have ever used
Hi Patrick

I don't think this shows any issue with the HF+ Discovery, just that the Hermes Lite 2 is a quite astonishing bit of kit for the money. Actually regardless of the cost. Punches way above its weight. I did always think so but this has just confirmed it for me. Unless I have a sub-par HF+? Wonder if you managed to watch my video recordings of the NDB?

Unfortunately I was not able to listen for Grimeton test transmissions today. Listening now but nothing heard so I guess too late to the game. I will be sure not to miss the main TX tomorrow morning.

Max


Re: NDB - Airspy HF+ DIscovery versus Hermes Lite 2

jdow
 

I suspect it is an issue with the antenna match to the receiver. One might provide better performance on any given antenna than the other. Which one does better depends on the antenna. And nothing says the better one cannot be improved upon with slight changes. This is down at a frequency range where antennas should not make any difference as far as QRM from outside the station's perimeter is concerned. But things such as wind can setup charges in wires it blows past. Front end impedance at DC can have significant effects on this. It might be entertaining, if the antenna is large (say a full size 80 meter dipole) to place an easily obtainable T connection and 50 ohm dummy load at the input of the receivers. If connecting the antenna raises the noise in both receivers the performance comparison should still face the same externally generated noise issue perhaps with less atmospheric effects differences on the antennas. The AirSpy's noise figure is do low that at any frequency under 10 MHz a 20 dB pad on a dipole antenna's feed line should not materially affect received SNR. So something else has to be creeping into the setup. Rain static? Wind effects? Really close by really high power AM radio station? That latter could exceed the AirSpy's dynamic range before it would affect something with an extra bit or two of A/D resolution. An AM band reject filter would mitigate this problem nicely. And it might improve both HL2 and AirSpy.

{^_^}

On 20211223 06:36:19, Max wrote:
On Thu, Dec 23, 2021 at 12:34 PM, Patrick wrote:
It's indeed surprising.
As a LF enthusiast (chasing NDB for more than 20 years), I can tell the Discovery is one of the most sensitive receiver I have ever used
Hi Patrick

I don't think this shows any issue with the HF+ Discovery, just that the Hermes Lite 2 is a quite astonishing bit of kit for the money. Actually regardless of the cost. Punches way above its weight. I did always think so but this has just confirmed it for me. Unless I have a sub-par HF+? Wonder if you managed to watch my video recordings of the NDB?

Unfortunately I was not able to listen for Grimeton test transmissions today. Listening now but nothing heard so I guess too late to the game. I will be sure not to miss the main TX tomorrow morning.

Max


Re: NDB - Airspy HF+ DIscovery versus Hermes Lite 2

Allan Isaacs
 

Max.. I’m overhauling a WW2 R1155 and as I tuned across the long wave band a Polish station close to Radio 4 came in at a good S8 about mid day.

I checked on my Andrus SDR with the same aerial and it wasn’t more than a tiny spike with no audible modulation

Admittedly the R1155 has been modified with a 6AK5 RF stage…

Allan G3PIY


From: main@SDR-Radio.groups.io [mailto:main@SDR-Radio.groups.io] On Behalf Of Max
Sent: 23 December 2021 14:36
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] NDB - Airspy HF+ DIscovery versus Hermes Lite 2

 

On Thu, Dec 23, 2021 at 12:34 PM, Patrick wrote:

It's indeed surprising.

As a LF enthusiast (chasing NDB for more than 20 years), I can tell the Discovery is one of the most sensitive receiver I have ever used

Hi Patrick

I don't think this shows any issue with the HF+ Discovery, just that the Hermes Lite 2 is a quite astonishing bit of kit for the money. Actually regardless of the cost. Punches way above its weight. I did always think so but this has just confirmed it for me. Unless I have a sub-par HF+? Wonder if you managed to watch my video recordings of the NDB?

Unfortunately I was not able to listen for Grimeton test transmissions today. Listening now but nothing heard so I guess too late to the game. I will be sure not to miss the main TX tomorrow morning.

Max

_._,_._,_

 


Re: NDB - Airspy HF+ DIscovery versus Hermes Lite 2

Max
 

On Thu, Dec 23, 2021 at 12:34 PM, Patrick wrote:
It's indeed surprising.
As a LF enthusiast (chasing NDB for more than 20 years), I can tell the Discovery is one of the most sensitive receiver I have ever used
Hi Patrick

I don't think this shows any issue with the HF+ Discovery, just that the Hermes Lite 2 is a quite astonishing bit of kit for the money. Actually regardless of the cost. Punches way above its weight. I did always think so but this has just confirmed it for me. Unless I have a sub-par HF+? Wonder if you managed to watch my video recordings of the NDB?

Unfortunately I was not able to listen for Grimeton test transmissions today. Listening now but nothing heard so I guess too late to the game. I will be sure not to miss the main TX tomorrow morning.

Max


Re: A new way to shut off a PC

jdow
 

Just a random observation - I tend to over-provision the power supply on general principles. It will stand up to random heavy spikes in load a little better. I don't believe what manufacturers claim for the power demands on their chips and boards better than +/- 25% to +/- 50%.

They last longer. But dirty power and surges have destroyed power supplies anyway.

{^_^}

On 20211223 06:26:08, Tom Crosbie G6PZZ wrote:
Yes they do David,
My GT1600 (Whatever Simon was recommending!) has a 4-pin connector (old school HDD type)
Mine is powered directly from the PSU. Not sure if any power is supplied via the graphics card slot as well in this case.
Never tried it without its power connection.
Although I'm an experienced desktop/server builder, I didn't want to take the risk of blowing a brand new (and quite expensive mobo!)
The XYL would have had something to say as the components were a gift from her! The shopping list came to around £900 without a PSU and case.
I can't stand the thought of throwing out working kit until it becomes completely obsolete and only got rid of some PCI graphics cards about 5 years ago...

Tom G6PZZ

-----Original Message-----
From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of David J Taylor via groups.io
Sent: 23 December 2021 13:48
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] A new way to shut off a PC

On 23/12/2021 12:46, Tom Crosbie G6PZZ wrote:
Max et al,

I have a Corsair PSU too can’t recall exact model but it’s rated at 
750W. It was overkill for the first PC I built with it and the second 
and probably the third one too, built last year. My first with a 
“good” graphics card. This PSU must be about 9 years old now and the 
PC runs 24/7, current uptime about a year except for update reboots. I think I’m getting my money’s worth out of it.

Tom G6PZZ
Do some graphics  cards have a second power supply connection?  I've seen this with satellite TV tuner cards.  Just wondering what might happen if the second power lead hadn't been connected....

David GM8ARV
--
SatSignal Software - Quality software for you
Web: https://www.satsignal.eu
Email: david-taylor@...
Twitter: @gm8arv












Re: A new way to shut off a PC

Allan Isaacs
 

David... Most new motherboards have a second connector (12V yellow/black)
which has to be plugged in for the system to boot up.
Some graphics cards also have an extra power connector, also 12V
yellow/black which looks similar to the type for the motherboard. Some early
graphics cards had a standard 5V/12V four pin connector.
These two yellow/black PSU leads can be plugged in back to front by mistake
which prevents the PC from booting up.
Both are only available on modern PSUs.
Allan G3PIY

-----Original Message-----
From: main@SDR-Radio.groups.io [mailto:main@SDR-Radio.groups.io] On Behalf
Of David J Taylor via groups.io
Sent: 23 December 2021 13:48
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] A new way to shut off a PC

On 23/12/2021 12:46, Tom Crosbie G6PZZ wrote:
Max et al,

I have a Corsair PSU too can't recall exact model but it's rated at 750W.
It
was overkill for the first PC I built with it and the second and probably
the
third one too, built last year. My first with a "good" graphics card. This
PSU
must be about 9 years old now and the PC runs 24/7, current uptime about a
year
except for update reboots. I think I'm getting my money's worth out of it.

Tom G6PZZ
Do some graphics cards have a second power supply connection? I've seen
this
with satellite TV tuner cards. Just wondering what might happen if the
second
power lead hadn't been connected....

David GM8ARV
--
SatSignal Software - Quality software for you
Web: https://www.satsignal.eu
Email: david-taylor@...
Twitter: @gm8arv


Re: A new way to shut off a PC

Tom Crosbie G6PZZ
 

Yes they do David,
My GT1600 (Whatever Simon was recommending!) has a 4-pin connector (old school HDD type)
Mine is powered directly from the PSU. Not sure if any power is supplied via the graphics card slot as well in this case.
Never tried it without its power connection.
Although I'm an experienced desktop/server builder, I didn't want to take the risk of blowing a brand new (and quite expensive mobo!)
The XYL would have had something to say as the components were a gift from her! The shopping list came to around £900 without a PSU and case.
I can't stand the thought of throwing out working kit until it becomes completely obsolete and only got rid of some PCI graphics cards about 5 years ago...

Tom G6PZZ

-----Original Message-----
From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of David J Taylor via groups.io
Sent: 23 December 2021 13:48
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] A new way to shut off a PC

On 23/12/2021 12:46, Tom Crosbie G6PZZ wrote:
Max et al,

I have a Corsair PSU too can’t recall exact model but it’s rated at
750W. It was overkill for the first PC I built with it and the second
and probably the third one too, built last year. My first with a
“good” graphics card. This PSU must be about 9 years old now and the
PC runs 24/7, current uptime about a year except for update reboots. I think I’m getting my money’s worth out of it.

Tom G6PZZ
Do some graphics cards have a second power supply connection? I've seen this with satellite TV tuner cards. Just wondering what might happen if the second power lead hadn't been connected....

David GM8ARV
--
SatSignal Software - Quality software for you
Web: https://www.satsignal.eu
Email: david-taylor@...
Twitter: @gm8arv


Re: A new way to shut off a PC

David J Taylor
 

On 23/12/2021 12:46, Tom Crosbie G6PZZ wrote:
Max et al,

I have a Corsair PSU too can’t recall exact model but it’s rated at 750W. It
was overkill for the first PC I built with it and the second and probably the
third one too, built last year. My first with a “good” graphics card. This PSU
must be about 9 years old now and the PC runs 24/7, current uptime about a year
except for update reboots. I think I’m getting my money’s worth out of it.

Tom G6PZZ
Do some graphics cards have a second power supply connection? I've seen this
with satellite TV tuner cards. Just wondering what might happen if the second
power lead hadn't been connected....

David GM8ARV
--
SatSignal Software - Quality software for you
Web: https://www.satsignal.eu
Email: david-taylor@...
Twitter: @gm8arv


Re: 137MHz "V" Antenna advice needed ...

David J Taylor
 

On 23/12/2021 12:38, Patrick wrote:
Would a similar V antenna, adjusted to the proper length, would be suitable for
ADS-B or even plane scatter (air scatter) ?
A collinear made from co-ax would be a better bet for 1.09 GHz ADS-B as it has
more gain. For example:

https://www.balarad.net/

For aircraft scatter use an antenna appropriate to the frequency you wish to
receive.

Cheers,
David
--
SatSignal Software - Quality software for you
Web: https://www.satsignal.eu
Email: david-taylor@...
Twitter: @gm8arv


Re: A new way to shut off a PC

Tom Crosbie G6PZZ
 

Max et al,

 

I have a Corsair PSU too can’t recall exact model but it’s rated at 750W. It was overkill for the first PC I built with it and the second and probably the third one too, built last year. My first with a “good” graphics card. This PSU must be about 9 years old now and the PC runs 24/7, current uptime about a year except for update reboots. I think I’m getting my money’s worth out of it.

 

Tom G6PZZ

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Max
Sent: 22 December 2021 22:35
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] A new way to shut off a PC

 

Agree power supply can caused weird faults. I had one where the PC could not be turned on with the front panel switch, but would turn on if the main AC outlet switch was cycled. Friend had same PSU (Seasonic) they no longer needed, but was identical model and age as we had got a deal by company to build our two PCs at same time to same spec, so he sent that to me. Tried that. Exactly same fault, so assumed PSU not at fault but then PC decided not to turn on at all. Changed motherboard, same fault again. As a last resort I bought a brand new PSU (Corsair). Turned on, all sorted. Incredibly, friend's PSU they had lent me must have had exactly the same fault on it. What's the chance of that?!

Had the new Corsair PSU now for maybe three years. No issues whatsoever. Possibly illogical, but will probably avoid Seasonic PSU again in future!

Max


Re: 137MHz "V" Antenna advice needed ...

Patrick
 

Would a similar V antenna, adjusted to the proper length, would be suitable for ADS-B or even plane scatter (air scatter) ?


Re: NDB - Airspy HF+ DIscovery versus Hermes Lite 2

Patrick
 

Hi Max,

It's indeed surprising.
As a LF enthusiast (chasing NDB for more than 20 years), I can tell the Discovery is one of the most sensitive receiver I have ever used, if not the most sensitive (among Perseus, ELAD S1, ELAD S2, RSPduo, RSPdx I had the opportunity to test).


Re: A new way to shut off a PC

Max
 

On Thu, Dec 23, 2021 at 12:07 PM, Allan Isaacs wrote:

Bon chance Michel

Allan G3PIY

Yes, good luck Michel. Yes, Allan, had assumed that it was likely to be caps. Quite interesting that obviously two PSUs of same make/design must have had same or similar caps fail at pretty much exactly same time. I suppose at least they were consistent. Reason my mate had his Seasonic spare was his mobo had gone too couple years earlier, so he bought brand new mobo and PSU. My mobo (Asus, same as one he had fail) is still going strong after many more years (touch wood) so at least not plagued on that score (yet). It's been pretty amazing actually, and apart from adding GTX1650Super to replace the onboards graphics (supercharged it I'm pleased to say) not felt any other need to upgrade so far even after more than 10 years use as it still does all I need and at good speed. Fingers crossed it keeps going!

73

Max


Re: A new way to shut off a PC

Allan Isaacs
 

Bon chance Michel

Allan G3PIY

 


From: main@SDR-Radio.groups.io [mailto:main@SDR-Radio.groups.io] On Behalf Of michel soldevila
Sent: 23 December 2021 11:53
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] A new way to shut off a PC

 

Ordered today a new 650W Cordsair PSU ... and thermal grease.
Michel, F1GOC

_._,_._,_

 


Re: A new way to shut off a PC

michel soldevila
 

Ordered today a new 650W Cordsair PSU ... and thermal grease.
Michel, F1GOC


Re: A new way to shut off a PC

Allan Isaacs
 

Your problem with the Seasonic was probably aging capacitors Max.

Lifetime of electolytics is an inverse function of temperature and some specific makes were very poor.

A PC PSU is basically always ticking over when powered up waiting for the trigger from the on off button.

When the button is pressed there’s an instantaneous check for current drain which if deemed excessive will prevent the DC voltages establishing. If a bad capacitor is present things will go awry with normal current deemed too high probably because proper voltages are not being established.

If you open the bad PSU case you would most likely see one or more capacitors with a bulging top.

The same problem capacitors plagued motherboards ten years ago.

Allan G3PIY


From: main@SDR-Radio.groups.io [mailto:main@SDR-Radio.groups.io] On Behalf Of Max
Sent: 22 December 2021 22:35
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] A new way to shut off a PC

 

Agree power supply can caused weird faults. I had one where the PC could not be turned on with the front panel switch, but would turn on if the main AC outlet switch was cycled. Friend had same PSU (Seasonic) they no longer needed, but was identical model and age as we had got a deal by company to build our two PCs at same time to same spec, so he sent that to me. Tried that. Exactly same fault, so assumed PSU not at fault but then PC decided not to turn on at all. Changed motherboard, same fault again. As a last resort I bought a brand new PSU (Corsair). Turned on, all sorted. Incredibly, friend's PSU they had lent me must have had exactly the same fault on it. What's the chance of that?!

Had the new Corsair PSU now for maybe three years. No issues whatsoever. Possibly illogical, but will probably avoid Seasonic PSU again in future!

Max

_._,_._,_

 

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