[Kenwood] TM-241A - Stop transmitting

[Ziv Amit]

Hi

Thanks for your following email... 

I open the power module and looked under a x20 microscope all traces are ok. I would also thing that if a trace would be open there would be no power at all, but I can get the high power running in the first 10-15 min of regular QSO..

After ~ 15min there in no output and then after another 10-15min I can get the power back on...

The power module I well connected to the heat-sink with conductive temperature paste.  

Any Idea?

 
Radion / Ziv Amit
Tel: 972-3-9226688
Fax: 972-3-9226655
Mobile:972-52-6522080
Skype user - zivamitoffice
Amatuer Radio Operator - 4Z4OQ

-----Original Message-----
From: Clif [mailto:avvidclif at wildblue.net] On Behalf Of Clif Holland
Sent: Wednesday, January 18, 2012 4:50 PM
To: Ziv Amit
Subject: Re: [Kenwood] TM-241A - Stop transmitting

Ok, the usual fault is the final module. It is made with traces on a ceramic substrate and over time the substrate will crack a trace from flexing. Many time locating the open trace and adding a jumper is enough to fix it. The cover can be popped off the module for troubleshooting. Lots of time the crack can be seen, usually shows up as a black hairline across the trace. 
Large magnifier needed.

Clif Holland KA5IPF
www.avvid.com




----- Original Message -----
From: "Ziv Amit" <ziv at radion.co.il>
To: "Clif Holland" <clif at avvid.com>
Sent: Wednesday, January 18, 2012 2:40 AM
Subject: RE: [Kenwood] TM-241A - Stop transmitting


Hi Clif



Thanks for answer. Its not 15 min hold of ptt, but regular qso it takes 
about 15 min until I see the problem



Radion / Ziv Amit

Tel: 972-3-9226688

Fax: 972-3-9226655

Mobile:972-52-6522080

Skype user - zivamitoffice

Amatuer Radio Operator - 4Z4OQ





-----Original Message-----
From: Clif [mailto:avvidclif at wildblue.net] On Behalf Of Clif Holland
Sent: Wednesday, January 18, 2012 3:57 AM
To: Ziv Amit
Subject: Re: [Kenwood] TM-241A - Stop transmitting



It's rated 1 min tx to 3min rx. Figure the ratio. 15 min is way too long.



Clif Holland KA5IPF

www.avvid.com









----- Original Message -----

From: "Ziv Amit" <ziv at radion.co.il>

To: <kenwood at mailman.qth.net>

Sent: Tuesday, January 17, 2012 3:39 PM

Subject: [Kenwood] TM-241A - Stop transmitting





> Hi

>

>

>

> I got a TM-241A that is stopping transmitting after a standard QSO of

> 15min. after 5-10 min it comes back to life.

>

>

>

> Any idea?

>

>

>

> Ziv Amit - 4Z4OQ

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