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> Helicopters & Parts > Gyro & Stabilization > Tail Gyro


Hobby King 401B AVCS Digital Head Lock Gyro

Hobby King 401B AVCS Digital Head Lock Gyro

The now famous HK401B is known to have the same characteristics as the Futaba GY401. In fact we guarantee you wont know the difference!
No tail drift, excellent hold characteristics and a level of reliability only found in $100+ gyros.
Dont risk your heli with other cheap Gyros when the HK401B has been proven by thousands of pilots to be stable and accurate in a variety of temperatures and helicopters.
Compatible with both Digital and Analog systems
Minimizes rudder trim changes caused by wind, other meteorological changes, and varieties of helicopter attitude changes are automatically cancelled.
Sensor vibration proofing
Simple sensitivity adjustment
Digital proportional RIC system
Operating voltage: 4.8V ~6V( common for receiver)
Operating temperature: -lOL r-.rf-45 C
Dimensions: 28x26x20 mm
Operating current: 80mA

IMPORTANT: Make sure you isolate your Gyro from vibration. Use double sided foam tape and never use cable ties. Vibration will cause harm to the Gyro and degrade performance.
Manual found in the files section below.


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Weight: 27g Quantity: 
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Price $11.99

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 Customer rated
Total of 527 discussions.
lolerblades  5 points - 8/27/2014
Awesome little gyro. Just make sure sensor is exactly parallel to the main board and hot-glued in place. 4F5FF23E-9D66-4056-A6D7-B03DCC8FF32F
Kevin  4 points - 8/23/2014
I have seen a few posts asking about the AVC AND NOR settings using the tx9 and have seen a few people complaining that they have no control in AVC mode (head holding). The settings have to be above 50. Set to these setting and i have found this gyro works very well and you can switch between head holding and rate mode with no problems using the switch. State ACT UPRATE AVC 068 DNRATE NOR 060 MODEL GY Make sure you have the other gyro settings on the gyro set up correctly too ,as the instructions.
joshua  1 points - 8/19/2014
can i connect this to the steering servo in a rc car
Jair de Souza  15 points - 7/21/2014
May I use this gyro with a helicopter with tail motor, no tail servo?
 TrDXFilms 73 points
Theoretically yes
 r_g_r 1288 points
No, this gyro put out a signal for servos. This is a PWM signal with long LOW and short HIGH periods. The length of the HIGH period defines how far the servo should travel. Your motor (I assume its non-brushless) needs a certain voltage to spin at a certain rate. The higher the voltage the faster it will spin. These are two totally different concepts.
 joao 2 points
ola eu posso utilizar um servo analó*gico neste giro
 Jair de Souza 15 points
Olá* Joã*o, sim, você* pode usar servo analogico com esse giro. Ele tem um um switch DS que você* liga (ON) para servo digital ou desliga (OFF) para servo analogico. Porem nao se esqueç*a que pra servo de cauda o recomendado eh usar servo high speed.
menandro  3 points - 7/17/2014
Poç*o usar com qualquer servo este gyro 401b
 Jair de Souza 15 points
Olah Menandro. Teoricamente sim! Ele tem um um switch DS que você* liga (ON) para servo digital ou desliga (OFF) para servo analogico. Porem nao se esqueç*a que pra servo de cauda o recomendado eh usar servo high speed.
Customer Reviews
Review Blogs for this item
gyro used for Esky HB King 3
Fly less, spend more.
Overall Rating
143 thumbs up!
Ensure you do the fix for this gyro. This is a pretty decent gyro at this price... HK Rocks.

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Overall Rating
68 thumbs up!
IMPORTANT 2-minute fix for this gyro: ("" slash "hk401fix")

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Overall Rating
17 thumbs up!
The gyro is amazing. I used it in the road car model to manage and everything is in perfect order. I recommend this product for its sensitivity and price.

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13 thumbs up!
i figured for the price i couldnt resist trying one of these and i am not dissapointed this things works great just as good as my 401 futaba gyro you need to look at the mods section on this as i had to do that but the little time i spent doing the mod was more then made up for with the low price and great performance

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Overall Rating
12 thumbs up!
I bought this gyro to try out for HK 450 it does very well ,hold the tail is solid with JR servo DS290G, First I received, inside board was sloppy & I try on heli it doesn't work, then I Open in back gyro I sim double tape to hold them inplace worked very well fly good,good for $ too

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