Programmable mosfet

[ButcherBill]

Hi Hive mind, there's loads of info about mosfets in the forums but I have a simple question that I can't find the answer to, is there a programable mosfet that will simply plug into/onto the wiring between the motor and the battery or are they all fitted into the gearbox?

I like the idea of being able to program an aeg to a burst mode if I wanted but don't have the skills or bravery to fit one into a gearbox.

 

If there is such a mosfet... what would you recommend?

 

TIA

Edited Saturday at 19:30 by ButcherBill

[Austeyr]

To my knowledge the only programmable mosfets go inside the gearbox. You might be able to adjust the ROF low enough to 3 round burst with a perun of some kind however, I seem to recall them offering such a thing 🤔

[Colin Allen]

The Perun AB++ or something similar is probably the closest to that as it sits outside the gearbox, but you do have to open the gearbox to do some rewiring unless you are fitting it to a V3 gearbox.

[Adolf Hamster]

As above the perun ab++ or its gate equivalent the warfet. There are other mosfets that do burst like the merf but tbh i wouldnt really consider them worthy competition.

 

Either way they'll need a seperation of wiring between the trigger contacts and the motor which for most gearboxes means cracking them open.

 

Thats one of the reasons i like the gate ecosystem, as if you wire the gun for a cheaper basic mosfet like the nanoasr then changing up to a warfet is a plug and play operation and you could theoretically swap one mosfet between multiple guns (if you note down the settings for each pew).

 

They have some disadvantages, specifically that because precocking is reliant on cutoff timing the first shot after a burst of auto wont be timed properly, which depending on your shooting style and disposition could range from inconsequential to annoying.

[Rogerborg]

14 hours ago, Colin Allen said:

you do have to open the gearbox to do some rewiring unless you are fitting it to a V3 gearbox

 

Repeated for emphasis. With a V3 gearbox, the trigger tabs protrude outside, so you can just solder the trigger wire onto them. I fitted a Perun AB++ to a G36 V3 without opening it.

 

You will have to do a bit of soldering though.  The only zero-effort solution is to pay a tech.

[ButcherBill]

Think I'll look at getting the Merf 3.2 mosfet...

 

1. It's a plug & play

2. I'm not confident at opening any gearbox & expect it to work properly (know your limitations)

3. I've not soldiered anything in decades

4. I should be able to use the same mosfet in several rif's

[Adolf Hamster]

Personally, i'd splash the extra for the warfet. The merf i found to be dissappointing and finnicky (read impossible) to properly program.

 

The warfet has more functionality (namely proper precocking) and the programming card is easy (if slow) to use.

 

Edit: worth noting that the wiring requirements for the merf and warfet are identical, so the warfet wont be any harder to install/swap between pews.

[Austeyr]

2 hours ago, Adolf Hamster said:

Personally, i'd splash the extra for the warfet. The merf i found to be dissappointing and finnicky (read impossible) to properly program.

 

The warfet has more functionality (namely proper precocking) and the programming card is easy (if slow) to use.

Second this whole heartedly 

[Colin Allen]

4 hours ago, Austeyr said:

Second this whole heartedly 

I third it; the Merf is awful.

[ButcherBill]

Oh, bugger.

[Adolf Hamster]

2 minutes ago, ButcherBill said:

Oh, bugger.

 

hopefully that's not a "got the despatch email before reading this" kind of oh bugger?

[ButcherBill]

7 minutes ago, Adolf Hamster said:

 

hopefully that's not a "got the despatch email before reading this" kind of oh bugger?

No, was waiting till payday anyway, just watching some YT clips about it.

[Adolf Hamster]

13 hours ago, ButcherBill said:

No, was waiting till payday anyway, just watching some YT clips about it.

 

Dodged a bullet then

 

Unfortunately the soldering (and depending on gearbox type dissassembly) is going to be on the cards for any mosfet that's using the original trigger components.

 

Personally i like the gate system, with the 2 signal wires to the trigger and 2 heavy wires to the motor as once you've gone to the trouble of soldering the gun the mosfet can be easily unplugged and moved to a new home.

[Rogerborg]

On 29/06/2025 at 20:36, ButcherBill said:

It's a plug & play

 

Re-re-emphasised, unless your gun is already wired for a mosfet, you'll have to do a bit of soldering.  Without a mosftet, the circuit is very simple, with the trigger just acting as a switch.

 

 

 

With a mosfet, the power wires run from the mosfet to the motor, and you'll need to rewire the trigger tabs as signal wires to the mosfet, generally using thinner wiring.  It's not complicated, just a few dabs of solder, but there's no avoiding it.  And you'll have to open the gearbox to do it, unless you have a V3 where the trigger tabs are accessible from outside.

 

 

[The_Lord_Poncho]

4 minutes ago, Rogerborg said:

And you'll have to open the gearbox to do it, unless you have a V3 where the trigger tabs are accessible from outside.

 

Same for the V7 (M14 etc)  which has the trigger contacts on the outside- about the only easier aspect of the V7!