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Perseus SDR IQ Recording Speed Issue

jwiedle@...
 

I've encountered an odd issue with my Perseus SDR Receiver. I record IQ spectrum files (2000 khz) with the native app (microtelecom software). However, when I go to play the IQ files back, the playback speed will be incorrect. It sounds almost like "Donald Duck" talking. I only seem to encounter this issue with my laptop and no other device.  I do not encounter this issue when I use 3rd party apps on the same device to record IQ spectrum files. Am wondering if anyone else has encountered this strange issue?  Thanks, WL7NO (James).

Robbert J. van Herksen
 

Which application are u using for playback??

 XS Max (512Gb)

On 8 Jul 2019, at 02:27, jwiedle@... wrote:

I've encountered an odd issue with my Perseus SDR Receiver. I record IQ spectrum files (2000 khz) with the native app (microtelecom software). However, when I go to play the IQ files back, the playback speed will be incorrect. It sounds almost like "Donald Duck" talking. I only seem to encounter this issue with my laptop and no other device.  I do not encounter this issue when I use 3rd party apps on the same device to record IQ spectrum files. Am wondering if anyone else has encountered this strange issue?  Thanks, WL7NO (James).

jwiedle@...
 

Hi, I am using the Perseus supplied software, ver 5.05b - V5 alpha version. 

barry williams
 

James,

What program were you using on the laptop? The Perseus program? What are the other apps you are talking about? Answers to those questions may get you the help you are looking for.


Barry


On Jul 7, 2019, at 7:27 PM, jwiedle@... wrote:

I've encountered an odd issue with my Perseus SDR Receiver. I record IQ spectrum files (2000 khz) with the native app (microtelecom software). However, when I go to play the IQ files back, the playback speed will be incorrect. It sounds almost like "Donald Duck" talking. I only seem to encounter this issue with my laptop and no other device.  I do not encounter this issue when I use 3rd party apps on the same device to record IQ spectrum files. Am wondering if anyone else has encountered this strange issue?  Thanks, WL7NO (James).

jwiedle@...
 

Hi Barry,

Let me provide some additional details. The issue I am dealing with concerns the playback of the IQ recording in the Perseus application. My recordings are done with 2000 khz sampling and the time of each I believe is approximately 8 minutes a piece. I will run the recording on the laptop anywhere from 4-6 hours.  The recordings are being done on an internal solid state 1 gig hard drive.  I've also tried the recordings on an external USB-C solid state hard drive resulting in the same problem. The problem is that roughly 3-4 hours into the recording, there appears to be a change in the playback speed of the recordings. They appear to speed up.

I have played the Perseus-originated recordings in SDR-Radio Ver 3 application and I experience the same issue. However, if I doing the actual recording in the SDR-Radio Ver 3 application, I do not have a problem with the playback speed.  

I should also note that I have used the Perseus supplied software in many of my other computers and have never experienced this issue, so I believe this is an issue potentially related to a driver conflict unique to this laptop. The computer in question is an ASUS Zenbook UX331UA. 

I suppose that I could just resign myself to only do my recordings in SDR-Radio Ver 3 but I do like the features of the OEM software!

Thanks

Bjarne Mjelde
 

James, when you say "change in playback speed", does this mean that perceived audio is faster? Or are recorded file sizes getting smaller? If the latter is the case, the problem may be lost data packets. A known issue with external HDDs but not with internal ones and certainly not SSDs. Anyway, the remedy is to configure the HDD for optimal performance.
If audio itself is faster, it's an issue I've never heard about. 
Maybe you should test version 4.1a one night to see if there may be software issues with version 5.

Bjarne Mjelde
arcticdx.blogspot.com

ubbe02@...
 

I agree that data loss during recording might be the problem, as that will be same as speeding up when playing back the file.
It sounds as if the laptop is going into battery/power saving mode after a couple of hours. Check those settings and try to use something
like game mode scheme or full power mode if those are preconfigured.

/Ubbe

jwiedle@...
 

Thanks for your suggestions. I disabled the sleep mode on the laptop and was able to resolve the issue!