# ?Design problem with Novak XXtra receivers?



## tfrahm (Nov 14, 1998)

On another thread, I posted about Wednesday night at our local indoor offroad track, when I had one of those nights where keeping 'Captain Bonehead' away from the transmitter was a full time job... Then in the Truck main, 2-3 times, my truck developed "mental problems" -- it was sort of a 'glitch', but it was more like it just shut off or lost the signal totally and it would just roll in the direction of it's momentum until it hit something and stopped... I'd get marshalled and it would be OK for a while... Then for the last half of the main, it seemed fine, but I was afraid to trust it... Weird -- guess I've got some work ahead of me to check this our... Bummer!

A friend posted:


> Tom, its time you came to the same realization I have for glitches: Novak XXtra receivers are junk. All three of mine have broken and Novak's lame excuse is "vibration damage". Now, they were cool enough to give me 3 brand new ones (didn't even have all the reciepts) but I'm sorry, these cars are going to "vibrate" while you drive. I figure those receivers are probably your problem because that is what mine were doing when they were giving out on me. Anywho, no more synthesized operation for me. I got rid of my radio as well. All crystals for me until the synthesized systems become more reliable.


I responded:


> Good guess... The MF2 has an XXtra synthesized receiver -- the concept is so good (fewer crystals needed, etc.), but their design leaves something to be desired... It's not the theory of synthesizing the frequency, because that should actually be LESS sensitive to vibration than a delicate crystal... NOVAK designed their XXtra receivers with a main circuit board and then a "daughter" board that stacks on top of the main board. The 'dials' are on the daughter board. The problem is that the two boards are NOT solidly joined -- instead of solder joints, there are small 'sockets' on the daughter board that simply slide onto 'pins' sticking up out of the main board. The fit is purely a friction fit, prone to vibration and loss of continuity. To make matters worse, the daughter board is roughly square, but is only attached at 3 corners, creating an unstable platform which tends to "rock" under vibration -- causing deterioration of the pin to socket contact due to wear and allowing the gold (?) plating to become damaged, allowing corrosion to occur. All of this could have been eliminated by using a fourth pin and/or joining the two boards by soldering the pins to thru-plated holes on the daughter board... Guess that's too complex a concept for them?


*The BIG question:*
Since my XXtra is out of warranty, I've wondered about taking the step of soldering the two boards together... 

*Anyone tried it?*


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## patcollins (Sep 29, 2001)

Tom

If it is a case of the daughterboard "vibrating" then one thing we do on electronic cards in military aircraft is tie a piece of "string tie" around the chip very snugly. This all but eliminates any problems caused by vibration. Let me tell you that you have no idea what vibration is until you fly in a H-60


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## gezer2u (Sep 25, 2001)

I have had the same experiance as you discribed. And it is the two boards mounting. I have even had the same problem with Futaba recievers in my airplanes. I have lost a couple of nice planes to the double board thing. Mybe some hot glue to hold the boards together. (shrug) I don't know.


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## Tres (May 10, 1999)

On the other hand, I have been running them since they became available....
With no issues, in both on & offroad.....

However, I could see where if the daughter board came loose it could cause some serious issues with the Rx components.

???


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## MIKE VALENTINE (Mar 12, 2002)

i love them, they run smotth as silk in my oval cars. most electrics don't handle crashes well, or 10 foot landings, you need to understand the nature of them. try dropping your vcr or tv and see how well it works.


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## Ron Hale (Sep 9, 2002)

Tfrahm,
I also had the problem you describe with the XXTRA receiver. I got T-Boned once on the receiver side. I also thought the problem was likely with the stacked boards. I was wrong. My problem was with one of the ceramic filters on the main board. It had no outward signs of failure. But, I, like you, was curious. Try this: open the receiver box, remove it from the case, and hook it up on the bench with a servo and speed control (or battery pack) plugged in. Take a small plastic screwdriver type tool (don't use metal) and while the receiver is on, plunk the components with the plastic tool and watch for failure as you're pokin' around. The ceramic filters are the 3 inline components on the bottom board, and they are about 1/4 inch square, and about the same height.
It really doesn't matter what component failed, since Novak has a replacement procedure for out of warranty products that is fairly reasonable. And, they don't repair your unit, instead they send you another. My XXTRA replacement cost $41.50 shipped. There is a form for you to print out on their website, and mail it along with the broken receiver. they turn around pretty quickly. I was satisfied. However, since I started using the JR synthesized receivers, I wont buy another novak.
Look on their website, www.teamnovak.com, select Customer Service, then scroll down to RETURNING A NOVAK PRODUCT FOR SERVICE, read about non-warranty items, and print out the pdf form. This form lists the prices for direct replacement. XXTRA rx = 32-bux, ship UPS Ground = 7.00, handling 2.50. 
Hope this helps.

Ronnie,
Cape Girardeau


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## FishRC (Sep 28, 2001)

Like any electronic part there will be some that fail. I have run XXTRA since it was available and run them hard. Off-road, Stadium and oval and have yet to have a failure. I have had the fewest glitches of any reciever I've used and the ones I did have were easy to fix. Broken wires and loose servo wires accounting for any issues I have had.


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## XXX-SCapece (Apr 28, 2004)

Are you using stick packs or saddle packs? I had that same problem with my Futaba, I descovered that the soldier wasn't making full contact with the bar, and during vibration, occassionally, the car would shut off, then come back on.


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## nutz4rc (Oct 14, 2003)

*Novak Receivers*

I have three of the synthesized and four XXLs; never had a problem with any of them. I run off road car and truck and oval legends as well as pan car. 

I have seen many batts have bars that broke loose. It sounds like the string around the boards might help. I also mount my receiver and ESC with velcro not tape. The velcro acts as a shock absorber.


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## elbowcreek (Apr 25, 2004)

I have one in a RPM rec. box on my GT and is packed in there tight with foam so it cannot move. Been using it for a couple of years now and no problems


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## chopperhead (Jul 4, 2004)

I have been through at least six of the Novak synthesized receivers myself. Great concept, but very prone to failure in my experience. Novak is always great about replacing them, but I get tired of sending them in. The reason they are calling them the Exxtra is because you need to keep an extra unit in your tool box in anticipation of the next failure. I have asked Novak several times if there is a problem, and of course they deny it, claiming they have had very few of the synthesized units come back. Yeah right. I like my orange equipment, but I think I am done with these receivers. Gonna try the new Airtronics unit.


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