[1000mp] Mark V Field Receive Desense

[Garry Shapiro]

This first happened to my MP in 1999 while QRV at 3B9R. Upon returning home,
I sent it to Yaesu in Los Angeles under warranty along with specific
instructions how to replicate the problem. Nonetheless, the tech claimed to
be unable to reproduce the situation, but he replaced a handful of parts,
including at least one relay. As with your case, the replaced parts were NOT
specifically identified, thus the act of returning the parts was useless.

The problem surfaced again several years later, and is still present
sporadically.

In prior discussions on this list, many subscribers have reported the same
problem. To my knowledge, Yaesu has never acknowledged it.

Garry, NI6T

-----Original Message-----
From: 1000mp-bounces at mailman.qth.net
[mailto:1000mp-bounces at mailman.qth.net]On Behalf Of Thomas Otterbein
Sent: Saturday, January 15, 2005 12:56 PM
To: 'All about Yaesu 1000mp'
Subject: RE: [1000mp] Mark V Field Receive Desense


Hi Hank,

I had a similar problem with my FT-1000MP Mk V Field as you, may
be caused by the same problem.
The receivers sensitivity going sometinme dramatically down.
A short push to the PTT brings the sensitivity back.
I could also repeat it by switching between the RX-Antenna and
Main-Antenna several times with the Rx-Antenna switch.
Sometime the muting also occur direct after switching on the transcv.

I found in my case that the the RL1002, RL1005 at the RF-Unit was
responsible for the muting. This relays had contact problems.

I send the  transceiver to YEASU, they repaired it an it works no.
The repair report was: exchanging relays at RF-Unit and modifying.
I didn´t get a response what they modified.

I believe my RX-Antenna (connected to the RX-Antenna input at the
transceiver) which is close to the transmitting antenna was the
reason. May be it brought to high rf-voltage to the relays.

I think the best way is to let it check by Yeasu.

By the way, in the 1000MP archieves you can find several messages describing
this circumstances.


73 de Thomas
DG8FBV
 ---
mailbox at Otterbein-INet.de
www.Otterbein-INet.de






> -----Original Message-----
> From: 1000mp-bounces at mailman.qth.net
> [mailto:1000mp-bounces at mailman.qth.net] On Behalf Of Hank Lonberg
> Sent: Samstag, 15. Januar 2005 20:46
> To: 1000mp at mailman.qth.net
> Subject: [1000mp] Mark V Field Receive Desense
>
>
> I have a fairly new 1000 MP Mark V Field. During the NAQP
> test just now and actually for some time now the receive
> desenses after I transmit. This doesn't occur every time but
> quite often. It takes 10 plus seconds to come back up to full
> value. This makes running a pileup hopeless as you can't hear
> the response. I had a very good run going on 15m and had to
> quit due to the problem.
>
> My question is what is the culprit and is there a fix?
>
> Thanks in advance
>
> Hank / KR7X
> IH9P Pantelleria Contest Team
> Tikirriki Contest Club
>
>
> _______________________________________________
> 1000mp mailing list
> 1000mp at mailman.qth.net http://mailman.qth.net/mailman/listinfo/1000mp
>

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