Yaesu: Yaesu VX-6 & VX-7 Receive Issue

[FKimble]

Send them in. They will inform you of cost and get your ok before repairing.

Frank

 

[MTS2000des]

Classic sign of front end filter failure. The issue is due to contamination of the filters. The write up on the V71A/D710GA covers it well and explains why it happens. Has little to do with storage.

 

[vagrant]

Oh wow. I didn't know those handhelds had bad TOKO filters in them too. I had that issue in two Kenwood D710's, but they (Kenwood) fixed both for free. I only had to pay shipping to them.

Yaesu VX-series sensitivity issue repair

Replacement for YAESU VX-6R VX-7R Signal Crash 450F Filter 3 PCS Bundle test | eBay

The filters are available from Yaesu parts. For CF2002, the manufacturer part number is ALFYM450F=k. The Yaesu part number, as listed in the service manual is H3900531. This part has been replaced by Yaesu PN H3900572A.

www.ebay.com

 

[SteveSimpkin]

The usual symptoms of a bad narrow-band 450kHzceramic filter is bad or no reception on pubic safety/ham radio using NFM but good reception on FM broadcast radio station using WFM.

Yaesu VX-series sensitivity issue repair

 

[k6cpo]

I have used the stock antennas...not working; put on the new antennas (from Amazon), still not working; simplex works for maybe 100 feet, then nothing. They can hear me loud, but I cannot hear them when they try to talk back. I did try one of the new antennas on a Wouxum & works perfectly.

ALthough both radios had been stored inside climate contolled room for about two years, they did work when I stored them. Now, nothing but paper weights! I find it quite odd that both radios have the same issue.

Not sure if it is cost-effective to have them checked out and/or repaired.

I think you need another set of eyes on the radios. Whatever is wrong, it's possible you're overlooking it and a fresh perspective might be able to figure out what's wrong. If you know someone knowledgeable that could take a look a the radios, I'd suggest doing that.

 

[lbashaw]

Finally, problem resolved! I sent the VX-6 to Yaseu service center in California. Excellent service attention and really fast turn-around. Problem was identified as a bad ceramic filter...replaced for less than $40. Now the VX-7 goes in to Yaseu.

 

[majoco]

Hang on a second - you said in the very first post " In simplex, both transmit & receive perfectly. " If the ceramic filter was bad as they say, how did it receive on simplex but not the very same signal when you interrogated the repeater. ? Doesn't make sense to me. I have a VX-2 18 years old somewhere round here, I'll give that a try and see if it suffers the same defect.

 

[KE5MC]

I think in the defense of the OP we typically don't appreciate signal strength at the device we are using especially in over the air situation. While the ceramic filter can fail like a light bulb, normally the symptoms are reduced receptions. Likely the original simplex to simplex might have been at 5w and a few hundred yards apart or less and powering thru the failing filter. When fixed the same test may be done at the lowest setting (100mw?) with the same 'perfect' results.

 

[MTS2000des]

Hang on a second - you said in the very first post " In simplex, both transmit & receive perfectly. " If the ceramic filter was bad as they say, how did it receive on simplex but not the very same signal when you interrogated the repeater. ?

Receiver will usually work in a strong signal (-10dbm from a nearby radio) but deaf to the "outside world". It's a well documented issue with ceramic filters and I have a stack of Kenwood 80 series mobiles made in 2006/2007 with the same issue. Deaf as a doornail on wide but work fine on narrow. Not worth fixing due to the labor involved.

 

[majoco]

"Simplex to simplex" has nothing to do with receiving the signal from the repeater.

 

[KE5MC]

...but it does have everything to do with establishing the RF signal path. We know the OP was hitting the repeater at 3 miles, but was not hearing the repeaters response. Unfortunately we don't know his working simplex range, nor do we know if he moved closer to the repeater and if he could eventually hear it. I'm betting he could if he tried. Signal path is about inverse-square law. Nothing in the repeater setup of power out or antenna gain was going to make up for a HT with a compromised receiver without moving closer to the repeater. Another HT in-close could easily overcome a failing filter because of proximity. As end users of the equipment we really don't appreciate the dynamic range the receivers have until they go from single digital microvolt sensitivity to 3 & 4 digit sensitivity (broken). What we normally hear at 3 miles has gone down to something much nearer. In this case using simplex was an easy way to eliminate repeater setup, but confused the issue when in hindsight it was poor sensitivity overcome by the proximity of the simplex transmitter.

 

[majoco]

When you enter the frequency of any repeater into your radio, you enter the repeater output frequency. If there is no tone squelch or other fancy stuff, you should be able to hear other users of the repeater. This is simplex, just like listening on a scanner. If you are in the service area of the repeater and you don't hear any chatter, then there is something wrong - too far from the repeater, poor receiver, bad antenna or coax, all the usual stuff - including finger trouble.

It's usual that the receivable distance from the repeater to your location is far greater than from your transmitter to the repeater - less transmitter power, local obstacles, less height, smaller antenna etc. Just because you can hear the repeater, doesn't mean you can hit it, but again - finger trouble.