RFX95HD Thermal protection?

[Hawkeye351]

I've installed several of these new add-on amps and had great success so far.

The only issues I'm hearing from people is the following:
After constantly talking on it for about 30 minutes, the amp gets scorching hot and power drops back to half the power output, then levels out around 70w to 80w.

Before I install any of these amps on any radio, I always put the radio back to stock condition, do a complete alignment, peak out the transmit, drop the key back to 4.5w and then is when I hook up and mount the amp. I then key up and adjust the deadkey to 15w instead of the 18w as stated.

The users are extremely pleased with the output, performance and gain these little things produce, it's just the heating issue. None of the radios I've installed them on will swing more than 38w maximum barefoot.

Any suggestions you guys/gals?

 

[Xracerx13]

Two 40mm Fans. That's what I would do. They all get hot even the original 75's and 85's. Its the nature of the beast.

 

[Hawkeye351]

Thank you for the quick response,
Any recommendations on supplier for ones that will mount up to these add-ons?

 

[Shadetree Mechanic]

Keeping the carrier low will help, but the heatsink is small so fans will make a big difference. It's the same with the RM Italy KL203, if you talk a lot, it needs a fan.

 

[codeman]

I had twin fans added to my Magnum S45 With the RFX 75 and it keeps it cool. I had it included when I bought the radio from Bell CB.

This isn't mine but looks just like it

 

[Xracerx13]

Any recommendations on supplier for ones that will mount up to these add-ons?

I usually get them on ebay or amazon. I look for brushless - ball or needle bearing - and that moves the most air (CFM). They are 40mm. But I would measure the heatsink to be safe. The 30mm's I use on 2510's because they mount easy, unless I upgrade to an MRF455 then I use 40mm's so there lies that confusion.

 

[Hawkeye351]

How would they mount on the heatsink? There are no screw holes on the heatsink except the 2 in the center to mount the amp.

 

[Xracerx13]

Some use a 1/2 inch of power wire and screw into that. Some use drywall anchors. Some use vac hose.
I use the power wire method. Push the power wire into the fin and screw into the center of the wire. It holds really well. It has to be wire that pushes into the fins real tight.
Then there's the Bells CB video shown above with large sheet metal screws but then you have to reem out the fan holes and the screw grabs the fins. I don't like that method.

I use this wire method on amps too, and if the fins are on the bottom like a texas star i use rubber feet that pull through and also hold fan guards on, in the outer fan screw hole closet to the fan guards.

For anyone else wondering about the HR2510 30mm fans.... there are 4 locations on the heatsink for each fan to screw into but you have to tap the holes. They are correctly spaced for 30mm fan mounting holes.