Topics

Frequency Floating


shaftan@...
 

Since the last update my SDR has been floating all over the place.  Any ideas?


Alan G4ZFQ
 

Since the last update my SDR has been floating all over the place.  Any ideas?
You have not told the users here what radio.
As you have been told in the Forum it is extremely unlikely to be due to the software.
But if someone has the same SDR and it is working normally, the same as before, then perhaps that will help to convince you.

Alan


Simon Brown
 

Alan,

He has the S2. I can't explain the frequency instability, maybe it needs to warm up?

Simon Brown, G4ELI
https://www.sdr-radio.com

-----Original Message-----
From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Alan G4ZFQ
Sent: 14 February 2021 12:43
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Frequency Floating

Since the last update my SDR has been floating all over the place.
Any ideas?
You have not told the users here what radio.
As you have been told in the Forum it is extremely unlikely to be due to the software.
But if someone has the same SDR and it is working normally, the same as before, then perhaps that will help to convince you.

Alan









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Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


shaftan@...
 

Elad FDM-S2


shaftan@...
 

Been running several days now.


Tony_AD0VC
 

Is it stable with the Elad SW2 software?

Tony


From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> on behalf of shaftan@... <shaftan@...>
Sent: Sunday, February 14, 2021 6:18 AM
To: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io>
Subject: Re: [SDR-Radio] Frequency Floating
 
Been running several days now.


Alan
 

On 14/02/2021 13:18, shaftan@earthlink.net wrote:
Elad FDM-S2
That is worrying.
What are you using to check the stability?
Is the power supply stable at the correct voltage?

Alan


jdow
 

The S2 is not advertised to have a TCXO let alone GPS lock. If it is a garden variety 50 ppm crystal he can expect as much as  1 kHz drift during warmup if he normally runs in a 50C room. Under more rational conditions 250 Hz drift would be a cold room to one around 29C inside the box as it warms. Lacking any other commentary, here or forum, I'd leave it as warmup drift and move on.

{^_^}

On 20210214 04:51:27, Simon Brown wrote:
Alan,

He has the S2. I can't explain the frequency instability, maybe it needs to warm up?

Simon Brown, G4ELI
https://www.sdr-radio.com 

-----Original Message-----
From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Alan G4ZFQ
Sent: 14 February 2021 12:43
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Frequency Floating

Since the last update my SDR has been floating all over the place.
Any ideas?
You have not told the users here what radio.
As you have been told in the Forum it is extremely unlikely to be due to the software.
But if someone has the same SDR and it is working normally, the same as before, then perhaps that will help to convince you.

Alan











jdow
 

So that still leaves room temperature drift, which is what your image on the forum showed.

{^_^}

On 20210214 05:18:25, shaftan@... wrote:
Been running several days now.


Simon Brown
 

Yes,

 

1Hz in 6 minutes isn’t bad, also when the radio is running it’ll get warmer than when it’s just switched on.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow
Sent: 14 February 2021 15:18
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Frequency Floating

 

So that still leaves room temperature drift, which is what your image on the forum showed.

{^_^}

On 20210214 05:18:25, shaftan@... wrote:

Been running several days now.

 


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Alan G4ZFQ
 

The S2 is not advertised to have a TCXO
Sorry Joanne, I was thinking it had a TCXO running for several days.
But I was confused, it is not a Duo, as Simon says 1Hz in 6 minutes is not bad for a normal crystal.

Alan


let alone GPS lock. If it is a
garden variety 50 ppm crystal he can expect as much as  1 kHz drift during warmup if he normally runs in a 50C room. Under more rational conditions 250 Hz drift would be a cold room to one around 29C inside the box as it warms. Lacking any other commentary, here or forum, I'd leave it as warmup drift and move on.


shaftan@...
 

It wasn't warming up.  It had been running all day and still floats.  Just calibrated with WWV on 10kHz and it is +2.2 PPM.  Let's see where it is later today.


n2msqrp
 

I don't know if this was discussed but does this occur with the ELAD FDM-SW2 software?
 
Mike N2MS

On 02/15/2021 7:13 AM shaftan@... wrote:
 
 
It wasn't warming up.  It had been running all day and still floats.  Just calibrated with WWV on 10kHz and it is +2.2 PPM.  Let's see where it is later today.


Simon Brown
 

Hi,

 

This really isn’t the software – could be the PC clock drifting but that’s highly unlikely.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of n2msqrp
Sent: 15 February 2021 13:24
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Frequency Floating

 

I don't know if this was discussed but does this occur with the ELAD FDM-SW2 software?

 

Mike N2MS

On 02/15/2021 7:13 AM shaftan@... wrote:

 

 

It wasn't warming up.  It had been running all day and still floats.  Just calibrated with WWV on 10kHz and it is +2.2 PPM.  Let's see where it is later today.


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n2msqrp
 

I suspect that is the case. That is why I would test with software supplied by the hardware vendor.
 
Mike N2MS

On 02/15/2021 8:45 AM Simon Brown <simon@...> wrote:
 
 

Hi,

 

This really isn’t the software – could be the PC clock drifting but that’s highly unlikely.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of n2msqrp
Sent: 15 February 2021 13:24
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Frequency Floating

 

I don't know if this was discussed but does this occur with the ELAD FDM-SW2 software?

 

Mike N2MS

On 02/15/2021 7:13 AM shaftan@... wrote:

 

 

It wasn't warming up.  It had been running all day and still floats.  Just calibrated with WWV on 10kHz and it is +2.2 PPM.  Let's see where it is later today.

 


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jdow
 

At the same time you note drift note the temperature within the radio. Graph them. I expect the frequency to go down as temperature goes up.

{^_^}

On 20210215 04:13:20, shaftan@... wrote:
It wasn't warming up.  It had been running all day and still floats.  Just calibrated with WWV on 10kHz and it is +2.2 PPM.  Let's see where it is later today.


W8RMV
 

Have you tried hitting it with a heat source like a hair blow drier to see if it is a temp issue?
--
Bob - W8RMV


shaftan@...
 

 If I can find one.  But it's been sitting in the same location for several years now and never a problem.


jdow
 

Have you added any new loads to our USB system? If the system is overloaded anywhere on the path to the S2 the voltage may drift and that will affect frequency.

{^_^}

On 20210216 06:19:45, shaftan@... wrote:
 If I can find one.  But it's been sitting in the same location for several years now and never a problem.


Simon Brown
 

1Hz over 6 minutes really isn’t a problem!

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of shaftan@...
Sent: 16 February 2021 14:20
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Frequency Floating

 

 If I can find one.  But it's been sitting in the same location for several years now and never a problem.


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