Ham International multimode II fault

[nav2010]

Just had this donated by a guy at work, turns on ok, TX/RX no problem until you've been TXing for 2-3 minutes then radio goes silent on am/fm/ssb. No RX or TX, turn the radio off, leave for 10 minutes, turn back on and radio works fine again. You can listen to the radio without TXing for about 15 minutes before the fault appears again. Seems like something is warming up or possibly overheating. Anyone any ideas about this intermitant fault?

 

[nav2010]

Problem sorted, was C11 a capacitor thats tired. Replaced and cured.

 

[nav2010]

Problem back again, looks like a PLL issue.

 

[RatsoW8]

I for one didn't know what a Ham International multimode II was until I googled it. Looks like a cb radio but its a 2 meter AM/FM SSB rig. Never heard of it. I made the giant leap in the 80's from Heathkit rock bound 2 meter mobiles to Kenwoods with a frequency display.

Looks interesting. Good luck with it.

 

[Robb]

The problem is no doubt heat related to use. Doubtful it is the PLL unless you have already back-tracked it to there. Get a can of compresses air and start spraying each part one at a time until it comes back on - sounds like a transistor that is thermally compromised. Check other parts if the transistor checks didn't solve the dilemma.

Doesn't hurt to look for iffy solder joints on the trace side of the board either.
Dull grey joints are possibly cold solder joints and can possibly be affected by heat too . . .

 

[nav2010]

My sollution is a plastic thing with wheels on we have over here called a wheely bin lol. Cybernet on SSB is a pile of crap anyway me thinks. May donate it to the local rig doctor for parts. Even the local rig doctor may feel the need to donate it to a wheely bin. Not spending anything on this pile, it looks like its been dragged to hell and back but thanks for the replies guys.

 

[ASHTEC]

Replace the VCO block......................

 

[tomaka0]

hi im looking for a multimode2 fascia any ideas

 

[Captain Kilowatt]

I for one didn't know what a Ham International multimode II was until I googled it. Looks like a cb radio but its a 2 meter AM/FM SSB rig. Never heard of it. I made the giant leap in the 80's from Heathkit rock bound 2 meter mobiles to Kenwoods with a frequency display.

Looks interesting. Good luck with it.

It's not a 2m radio. It is a CB radio of sorts.


http://ham-international.nuxit.net/MultimodeEng.htm

 

[Captain Kilowatt]

I should have looked at the thread date I guess.

 

[RatsoW8]

But you are right...I can't remember why I thought it was a 2 meter radio. It's a 10 meter radio...wink wink.