Distorted Sound + Pictures wanted

[[e-mail] [YaesuVR-5000]]

Hi,
I have been using my VR5000 for a while now and am enjoying it greatly.


One thing I have found is that after about an hour or so of listening, the sound becomes distorted.


I plugged in an external speaker and the distortion goes away. So I thought it might be the internal speaker.


However, I took the internal speaker out and plugged it into the external socket. No distortion after several hours of operation. Strange.


Having a look at the circuit diagram, there is a 4.7 ohm 1 watt resistor (R3005 on IF unit) in series with the loudspeaker. The resistor is not connected when using the external speaker socket.


I suspect that the resistor is increasing in resistance as it warms up.


Has anybody else had this problem ?


Also, my VR5000 did not come with the original feet and front bail. I would appreciate it very much if someone could take some pictures of the bottom of their unit and post it in the pictures section.


Cheers,
Mal
(Enthusiastic owner of a VR5000)

[[e-mail] [YaesuVR-5000]]

Hi, I have investigated this further. I took out the IF board and checked the 470 ohm resistor. I checked out OK, even when heated. I inspected the joints around the speaker socket and while they appeared to be all-right I decided to re-soldered them anyway.


I then put the radio back together, and let it play. After about an hour the sound became distorted again.


So, I decided to pull the internal speaker out and let the radio play, with the speaker sitting outside of the case. The distortion slowly got better and went away.


What had changed ? When I pulled the speaker out, it was warm from the heat of the radio's electronics. Once outside it started to cool down.


To be 100% certain, I have to test further by warming the speaker to see if the distortion comes back, but I am fairly sure that the internal speaker has a heat related problem that causes the distortion. Subtle indeed !


Now to find a replacement.


I still need pictures of the bottom on the radio showing the feet and the front bail. So I would appreciate it if some kind member of this group would take some and post in the photos section of this group.


Cheers,
Mal

[Jim Jordan [e-mail] [YaesuVR-5000]]

I imagine that the voice coil in the speaker could expand with the heat and rub in the gap, causing distortion. There is a liquid called ferrofluid (a magnetic liquid) that some speaker manufacturers put in the gap to extract heat and keep things from scraping will send a pic of the bottom of my unit and post to forum photos at some point.

-----Original Message-----
From: "***@Telstra.com [YaesuVR-5000]" <YaesuVR-***@yahoogroups.com>
Sent: ‎7/‎1/‎2014 5:47 AM
To: "YaesuVR-***@yahoogroups.com" <YaesuVR-***@yahoogroups.com>
Subject: [YaesuVR-5000] Re: Distorted Sound + Pictures wanted


Hi,
I have investigated this further. I took out the IF board and checked the 470 ohm resistor. I checked out OK, even when heated. I inspected the joints around the speaker socket and while they appeared to be all-right I decided to re-soldered them anyway.


I then put the radio back together, and let it play. After about an hour the sound became distorted again.


So, I decided to pull the internal speaker out and let the radio play, with the speaker sitting outside of the case. The distortion slowly got better and went away.


What had changed ? When I pulled the speaker out, it was warm from the heat of the radio's electronics. Once outside it started to cool down.


To be 100% certain, I have to test further by warming the speaker to see if the distortion comes back, but I am fairly sure that the internal speaker has a heat related problem that causes the distortion. Subtle indeed !


Now to find a replacement.


I still need pictures of the bottom on the radio showing the feet and the front bail. So I would appreciate it if some kind member of this group would take some and post in the photos section of this group.


Cheers,
Mal

[[e-mail] [YaesuVR-5000]]

Hi Jim, Thanks for the comments. Don't worry about the pictures as I have been sent some by another member. Cheers, Mal