Does anybody have a machine shop?

[rabbiporkchop]

I was thinking about having these heatsinks machined off and Polished flat so I could attach a genuine heatsink With more Surface area capable of dissipating more Heat.
The Machinist that did all my work passed away back in March so I'm looking for a new Machinist.

 

[Sonar]

I was thinking about having these heatsinks machined off and Polished flat so I could attach a genuine heatsink With more Surface area capable of dissipating more Heat.
The Machinist that did all my work passed away back in March so I'm looking for a new Machinist.

I needed a machine shop myself at one point. I just Googled machine shop and added my zip code. I found several located so close to my qth without ever knowing they were there.. I found one 5 miles away that did the work I needed for a very fair price. Good luck. 73

 

[Robb]

What's wrong with the original heatsink?
If anything, adding a fan should suffice.

 

[rabbiporkchop]

What's wrong with the original heatsink?
If anything, adding a fan should suffice.

Original is a bad design. Not enough surface area.

 

[fourstringburn]

Use 2 fans!

 

[rabbiporkchop]

Use 2 fans!

The heat sink is a bad design and the only thing that would improve it would be a constant flow of nitrogen blasting onto the heatsink which is kind of cost-prohibitive. it would be a lot simpler to machine those heat absorbers off the back and put an actual heatsink on it with a couple fans

 

[fourstringburn]

That heat "absorber" looks adequate, you ever see how small the heatsink is on the Galaxy 95 or the RCI 6300?

It's because they have fans! The heatsink pulls heat from the radio and the fan pulls heat from the heatsink so a small heatsink is all that is needed.

Are you driving your radio hard with a lot of deadkey trying to squeeze out every watt? All that does is build up excessive heat. Your radio shouldn't be getting that hot to begin with.

 

[Robb]

The heat sink is a bad design and the only thing that would improve it would be a constant flow of nitrogen blasting onto the heatsink which is kind of cost-prohibitive. it would be a lot simpler to machine those heat absorbers off the back and put an actual heatsink on it with a couple fans

Heatsinks - like that - have been used in 2m mobile radios for some time now w/o being an issue. If you are concerned about blowing up MOSFETs on a regular basis; then I'd suggest just not pushing them that hard. 50w from a dual final MOSFET is par for course and should not be exceeded, even if they are cheap to replace.

2m radios often have a fan installed with that kind of heat sink and final failures are almost non-existent.

 

[543_Dallas]

Sounds like you're just running it too hard man. Hopefully you can find a qualified tech to get this resolved.

 

[Road Squawker]

Original is a bad design. Not enough surface area.

speaking of a bad design,.... look at the data jack

 

[rabbiporkchop]

Sounds like you're just running it too hard man. Hopefully you can find a qualified tech to get this resolved.

Fortunately I don't have any issues as long as I respect the duty cycle. If you happen to know of any good technicians that can replace the mosfets with a pair of mrf 477 finals for less than $100.00, I'd be curious who that technician might be since that would cut my heat in half and easily double or triple my gain.

 

[rabbiporkchop]

That heat "absorber" looks adequate, you ever see how small the heatsink is on the Galaxy 95 or the RCI 6300?

It's because they have fans! The heatsink pulls heat from the radio and the fan pulls heat from the heatsink so a small heatsink is all that is needed.

Are you driving your radio hard with a lot of deadkey trying to squeeze out every watt? All that does is build up excessive heat. Your radio shouldn't be getting that hot to begin with.

It's not getting very hot at all considering I'm very conservative with how long I allow it to remain keyed.
If I wanted to ratchet jaw for hours at a time that's where the problem would present itself.
I'd love to be able to mount one of these on the back. Lots of thin fins with lots of surface area is much better than some big fat chunks of aluminum.

 

[Captain Kilowatt]

Heatsinks - like that - have been used in 2m mobile radios for some time now w/o being an issue. If you are concerned about blowing up MOSFETs on a regular basis; then I'd suggest just not pushing them that hard. 50w from a dual final MOSFET is par for course and should not be exceeded, even if they are cheap to replace.

2m radios often have a fan installed with that kind of heat sink and final failures are almost non-existent.

That heatsink looks pretty much like the one on my FT-857 but it also has a pair of small fans to remove heat from the inside of the radio. It is quite adequate for the 100 watts output.

 

[543_Dallas]

I think you'd be surprised at how much some airflow would help.

Is this the radio you were saying would deadkey 20 watts not too long ago? Did Mark at fine tune cb set it up like that?

 

[fourstringburn]

I think you'd be surprised at how much some airflow would help.

Is this the radio you were saying would deadkey 20 watts not too long ago? Did Mark at fine tune cb set it up like that?

Don't go there!!!