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I recently picked up a nice little Hitec Shredder RCD 75mhz AM receiver, however it's marked AIR so I presume it's tuned for Airtronics. There's no real wiring markings on it and I have no 75mhz AM Airtronics radio. Is there any way to test this receiver with a Futaba radio? Any thoughts?
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It will work with a Futaba transmitter, just use a Futaba crystal. Airtronics crystals are different than Futaba/JR/Hitec in 75mhz.

The wiring will be old Airtronics style.

Instead of "signal, positive, negative", I think they are "positive, negative, signal".

But you should do some more research first. If wired wrong, it will definitely destroy a servo, probably an esc.

I looked into the wiring and have made some adapters. I also have a couple of old Airtronics servos, so I tried those. I don't think the receiver likes Futaba radios and/or crystals. When I hook up Airtronics servos and a 4 cell pack, the servos will give a 'power on' twitch but will not move under radio command. I've tried a couple of different sets of genuine Futaba crystals and also an aftermarket set. I guess next I'll have to see if I can find either a set of Airtronics crystals or an Airtronics radio.

I have a Dynamite Micro Pro receiver, setup for Airtronics. Other than color, it is identical to a Shredder.

It does the same thing. But even in its manual, it just says to use crystals that match your transmitter.

But I also have real vintage Airtronics receivers that work fine with Futaba and JR radios. If real Airtronics, Futaba, and JR stuff works together, aftermarket parts designed to work with them should as well.

I've always just assumed that it was a bad receiver. I have another that is wired for Futaba that works fine.

You'll probably need an Airtronics crystal in the receiver, and a Futaba transmitter crystal in the transmitter - on the same band/frequency. If memory serves...one is positive shift, and the other is negative shift (don't remember which). But it's a matter of the crystal actually functioning in the receiver. I have older Novak NER-2S receivers for Futaba (with Futaba rx crysatl) that operate correctly with Airtronics XL2p's (with Airtronics Tx crystal).

I'll get an Airtronics AM rx crystal and give it a try. I'll be happy if it works but not super disappointed if it doesn't.

You should contact Hitec and find out if the positive and negative servo/esc plugs are reversed from the Futaba wire standard- if the plug shape on the receiver case is the shape of the old Airtronics plugs.

Mark Westerfield wrote: ↑Mon Oct 03, 2022 4:35 pm You should contact Hitec and find out if the positive and negative servo/esc plugs are reversed from the Futaba wire standard- if the plug shape on the receiver case is the shape of the old Airtronics plugs.

Hitec plus are wired the same as Futaba, as are newer Airtronics plugs.

Other plugs can be trimmed down to fit the Airtronics case.

The old style Airtronics plugs are a good fit in this receiver. I have a pair of old Airtronics servos that I never thought I'd have a use for. Receiver testing is there new purpose.

Using an Airtronics rx crystal for the receiver is the magic solution. The little Shredder works just fine with my Futaba radio now. Awesome!
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Frankentruck wrote: ↑Fri Oct 07, 2022 4:21 pm Using an Airtronics rx crystal for the receiver is the magic solution. The little Shredder works just fine with my Futaba radio now. Awesome!

Thanks.

I'm going to get one and give this Micro Pro another try.

Here it is, with a Shredder. Other than color and the label, they look identical. I have another Micro Pro (Futaba) and a couple Shredders.

That Dynamite MicroPro has old style Airtronics servo sockets, so it should need a Airtronics crystal. But be mindful, old style Airtronics plugs had the positive and negetive wires in reverse order from Futaba plugs. The Shredder receiver has Futaba style servo sockets.

Mark Westerfield wrote: ↑Mon Oct 10, 2022 8:35 am That Dynamite MicroPro has old style Airtronics servo sockets, so it should need a Airtronics crystal.

I have two, Futaba and Airtronics versions. The manual says to use crystals that match the transmitter.

Mark Westerfield wrote: ↑Mon Oct 10, 2022 8:35 am But be mindful, old style Airtronics plugs had the positive and negetive wires in reverse order from Futaba plugs. The Shredder receiver has Futaba style servo sockets.

I posted that picture for Ed, as he has the Shredder in Airtronics format. They are together to show the similarities.

Just to follow up on this. I did finally get an Airtronics receiver crystal to try.

I used a Futaba transmitter and crystal.
-Novak Polaris for Airtronics (with Futaba J plugs!).
-Dynamite Micro Pro for Airtronics.

Both worked when using an Airtronics receiver crystal on the same frequency. Neither would do anything with Futaba or Hitec crystals.

Strangely enough, my actual Airtronics receiver will function with a Futaba crystal in it. Glitchy, but functional.