XTL5000 + VRS750 = Poor Audio Quality. Guru advice needed.

[MotFAN]

Hi all!

I am experiencing poor audio quality when I listen portables with In-Car Monitor or on Base station side. When VRS is enabled, portable radios sounds quieter, like is 'from afar', and more deaf (like is smb talk to rear side of mic/or through the blanket). Speech is recognized, but it sounds insufficiently clear and quality.

• But when I monitor portables uplink frequency by another receiver (not VRS), they are sounds good. Channel bandwidth is 25 kHz and matches (I mean portables and VRS). Portables are high-tier, like XTS, but also I tried hamradio gear - same hell. So problem is not with portables or CH BW setting.
• Mobile XTL per se sounds good on reception (when signal come from air, but not VRS)
• Also conversations received by portables through VRS sounds good.

So problem is only when VRS receive portables.

The problem could be in Mobile Deviation Level, but I think it is not so. Because I also hear a poor quality sound from portables from In Car monitor.

Checked VRS SM, but there is nothing about VRS audio adjustment on RX.

VRS750 is P2081A with W492AG option (what means that it's intended to be used with XTL). Purchased used off eBay.

Radio is XTL5000 with factory tuning. New and was never in issues.

Any ideas?

P.S.
I think that this repeater should sounds good in any way. It's because Waris portables have very good audio frequency response. Repeater built from 2 Waris radios had no such problems (from my experience).

 

[MotFAN]

How to check a radio model that is VRS configured for? XTL or Astro Spectra?

 

[MotFAN]

Here is audio. It's recorded in-car by using iPhone, but it's still ok to evaluate dramatic lack with audio level (I measured approximately -12 dB) and poor sound quality when VRS is used.

:wtf:

 

[MotFAN]

Can it be a Rated Volume issue?

 

[Alpha]

That looks like a pretty exact audio level that it's looking for. I would try setting that first, and see if it fixes the problem.

 

[MotFAN]

That looks like a pretty exact audio level that it's looking for. I would try setting that first, and see if it fixes the problem.

You mean to pass through Rated Volume tuning procedure?

 

[Alpha]

Yes, it sounds like volume level is critical and is probably required for proper operation. I would go through it completely first, and see if it resolves the problem.

 

[MotFAN]

I will do, but it's not easy. I need to built programming cable, revmove VRS, and get access to generator and RMS voltmeter.

I will update this thread later.