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ayash · 12-07-2008, 05:30 PM

Looking into various web sites looking for a good deal on G770 I noticed there are two packages labeled as G770T and G7703D.

See below a question (unanswered) with photos of the two

http://www.runryder.com/helicopter/t380119p1/

Can anyone explain the difference? Is it the same only in a different package? Or two different gyros?

TheBum · 12-07-2008, 05:47 PM

I think they're the same gyro. I believe one (the 'T') is the European packaging and the other (the '3D') is the US packaging. Finless mentioned something in his G770 videos about getting the European packaged version.

mjbrands · 12-08-2008, 04:56 AM

Quote:

Originally Posted by TheBum

I think they're the same gyro. I believe one (the 'T') is the European packaging and the other (the '3D') is the US packaging. Finless mentioned something in his G770 videos about getting the European packaged version.

He got a JR 770T for his Protos build videos.

heliaddict22 · 01-05-2009, 01:04 AM

is this a good gyro? would you put it in T-REX 250?

Finless · 01-05-2009, 10:35 AM

I dont think this gyro will fit in a Trex250.

Bob

Kratos · 01-05-2009, 10:55 AM

First of all, thank you for the videos, very, very helpful. It's allways better to see what's going on. I have the 7703D on my 450SE and, with your help, have been able to finally get it set to where it is back in flying order. I just got the Align 500E scale fuse for it. I am going to have to remount the servo (S9650) from the side to straight under the boom to get it to fit and possibly install a new control rod (came with fuse).
Any imput, or will I just need to fly and try?
I know that this gyro is pickey and also likes a certain control rod length.
Any insight, sugestions or ideas will be apreciated.
Thanks

TheBum · 01-05-2009, 10:59 AM

Quote:

Originally Posted by Finless

I dont think this gyro will fit in a Trex250.

Agreed. A GY401 barely -- and I mean barely -- fits (at least if a buddy of mine's 250 is any indication) and the G770 is taller.

mr wokka · 01-12-2009, 05:35 AM

Hi Bob great vids by the way do you use Expo on the JR770 as i have piro rate set through Dual rates some say you should dial in 40% Expo true or not thanks
Dave.........

Pinecone · 01-12-2009, 09:30 AM

The JR doesn't ahve expo set IN the gyro like most. So 40% expo is like 0% on most other gyros.

So I would start by dialingin 50% expo before flying, then tweak to your preference.

ken22golf · 01-31-2009, 01:02 AM

I've read through the thread that got Bob into doing this video review (Spartan vs 770 3D), I watched his field test video, and read through every page of this thread.

I have not seen Bob's actual opinion on the performance of this gyro.

If someone has seen it, if you point it out, I would appreciate it.

If he hasn't given one, I would appreciate hearing your (Bob's) official opinion about the performance of this gyro.

I was thinking about upgrading from my 401, because this inconsistent piro rate (especially in windy conditions) is starting to bug me.

As always, thank you Bob for all your work and putting up with all (us) newbies. I couldn't have successfully gotten started on my own without your vids and the help of all the HF members.

TheBum · 01-31-2009, 07:19 AM

The one weakness it has IMO is the brutally abrupt stops at the end of piros. Some people have actually reported stripping torque tube gears from it stopping so fast. It's nothing that can't be overcome by changing the way you stop your piros, i.e. easing your way that last little bit to center stick.

It holds rock solid in a hover. When I was breaking in the engine on my T-Rex 600N, the tail held steady even with a brisk crosswind. The piro rates have been consistent left and right, certainly *much* more so than the 401 on my Diablo.

Pinecone · 01-31-2009, 07:34 AM

More expo.

Remember the 770 3D doesn't have ANY interanl expo. So 40% expo is like 0% on other gyros. You want to use 50 - 60% expo with this gyro.

ken22golf · 02-02-2009, 11:40 AM

Quote:

Originally Posted by ken22golf

I've read through the thread that got Bob into doing this video review (Spartan vs 770 3D), I watched his field test video, and read through every page of this thread.

I have not seen Bob's actual opinion on the performance of this gyro.

If someone has seen it, if you point it out, I would appreciate it.

If he hasn't given one, I would appreciate hearing your (Bob's) official opinion about the performance of this gyro.

I was thinking about upgrading from my 401, because this inconsistent piro rate (especially in windy conditions) is starting to bug me.

As always, thank you Bob for all your work and putting up with all (us) newbies. I couldn't have successfully gotten started on my own without your vids and the help of all the HF members.

Yeah, I was wondering the same thing

Where does it sit compared to others?

I have a 7703D w/ 3500G coming that I didn't expect to win on ebay (for $150) and I didn't know if it would be worth the trouble to switch it out. (vs 401 w/ 9257)

Finless · 02-02-2009, 01:24 PM

Well comparing the Spartan to the JR770 is an apples to oranges comparison!
The Spartan has far more adjustments and features and can be tweaked more to a certain pilots liking.... If the price of these 2 gyros was the same, I would go with the Spartan any day.

Bob

Hercman · 02-11-2009, 07:26 AM

First I must say I have found Finless Bob's how to videos amazing. They have been instrumental in learning all about my TREX 450.....as a "planker" I had some knowledge of R/C toys however very little on helos and setup. Thanks Bob!

My issue and question is related to setting up a JR 770 gyro on a TREX 450 with a JR XP7202 radio. I have set up the gyro according to the instructions and Bob's tutorials. The gain lead is on my GEAR channel and I am using gear travel adjustment to set it. When I have the travel adjustments both + and -set to 0%, the tail servo moves left and right coming back to center each time when the stick is centered. If I add some gain on the + side (have tried 30-60% on travel adjust), moving the rudder stick causes the servo and tail rotor to move and just as in the videos, it will not completely return to center since there is gain set in the travel adjust. My problem is that when I move the tail left and right, the gyro is not sensing tail movement and NOT compensating by feeding in tail rotor pitch. I have tried everything I can think of and am still stuck

All else appears to be operating as it should and the gyro and servo (JR3500) are both brand new.
Can anyone help me out troubleshooting this one? Iwould appreciate any suggestions on this matter. I am convinced it is a setup issue but don't know enough to sort the problem out.

Empot · 02-12-2009, 02:27 PM

I was using this gyro initially with a S9254 servo and I was getting some wag when turning but none in hard 3d. I upgraded to a 8900G servo and I never looked back since. I dont have problems with it even on fast piro's my expo is 50 and my gain on dx7 is 63 on gyro menu using KBDD blades. I find it its better with KBDD than the stock CF blades. backwards flight really holds well even when I try to push it really hard. Im very happy with it.

Pinecone · 02-13-2009, 11:36 PM

Quote:

Originally Posted by Hercman

First I must say I have found Finless Bob's how to videos amazing. They have been instrumental in learning all about my TREX 450.....as a "planker" I had some knowledge of R/C toys however very little on helos and setup. Thanks Bob!

My issue and question is related to setting up a JR 770 gyro on a TREX 450 with a JR XP7202 radio. I have set up the gyro according to the instructions and Bob's tutorials. The gain lead is on my GEAR channel and I am using gear travel adjustment to set it. When I have the travel adjustments both + and -set to 0%, the tail servo moves left and right coming back to center each time when the stick is centered. If I add some gain on the + side (have tried 30-60% on travel adjust), moving the rudder stick causes the servo and tail rotor to move and just as in the videos, it will not completely return to center since there is gain set in the travel adjust. My problem is that when I move the tail left and right, the gyro is not sensing tail movement and NOT compensating by feeding in tail rotor pitch. I have tried everything I can think of and am still stuck

All else appears to be operating as it should and the gyro and servo (JR3500) are both brand new.
Can anyone help me out troubleshooting this one? Iwould appreciate any suggestions on this matter. I am convinced it is a setup issue but don't know enough to sort the problem out.

Are you sure? The tail pitch slider will move slightly (more the faster you move the tail) while the heli is being rotated, but it will come back a bit when you stop. So you have to watch carefully, WHILE you rotate the heli.

Redfire SVT · 02-17-2009, 09:31 PM

Just in case someone needs to print off the manual: http://www.jrradios.com/ProdInfo/Fil...structions.pdf

Redfire SVT · 02-18-2009, 09:40 PM

Half way down page the 770 is setup for a Trex 500. http://madcow-productions.com/mluciaheli/?p=22

povern · 03-21-2009, 08:32 PM

So I watched the Gain 101 video, and the formula given for finding true gain using end points is:

endpoint / 1.44 = true Gain

But when I watch the video, when Bob sets the end point at 150, the gyro reads 113 and in another spot when the endpoint is 32, the gyro reads 25

The formula used to match these numbers is: endpoint / 1.33

What am I doing wrong? Just want to know what the gain is that I'm currently running before I go to the gyro menu, and start setting up my 7703d.

povern

12-07-2008, 05:47 PM	#222 (permalink)
TheBum HF Support My HF Map location Join Date: Jul 2007	I think they're the same gyro. I believe one (the 'T') is the European packaging and the other (the '3D') is the US packaging. Finless mentioned something in his G770 videos about getting the European packaged version. __________________ Alan (just call me "Bum"; no need to be so formal) HeliFreak Support Protos Max Evo 700 (Brain 2), Protos Max V2 770 (iKON 2), Synergy 516 (Brain 2), Oxy 2 (Falcon 12) Graupner MZ-32 Experience is something you gain only after you need it. I wouldn't mind social media so much if it didn't involve people.

01-05-2009, 10:35 AM	#225 (permalink)
Finless Team Taco VP Thread Starter My HF Map location Join Date: Nov 2005	I dont think this gyro will fit in a Trex250. Bob __________________ "Don't Taco My Pack Dude!" NEW Video Link -> Safety Video #1 Video Link -> CAUTION using powerful tools! Video Link -> How to CRASH TWICE in one flight! Video Link -> Don't Taco!

01-12-2009, 09:30 AM	#229 (permalink)
Pinecone Registered Users Join Date: Sep 2006	The JR doesn't ahve expo set IN the gyro like most. So 40% expo is like 0% on most other gyros. So I would start by dialingin 50% expo before flying, then tweak to your preference. __________________ Terry AMA#47402, IRCHA # 3395 Blade CP "Pro", Trex 450SE, PiccoZ, Quick of Japan EP8v2 EX, Hurricane 550, Hurricane 200, JR Vibe 50, Blade mCX, Bergen Intrepid Gasser, Pantera 50, Blade mSR, Novus CP

01-31-2009, 01:02 AM	#230 (permalink)
ken22golf Registered Users My HF Map location Join Date: Sep 2008	I've read through the thread that got Bob into doing this video review (Spartan vs 770 3D), I watched his field test video, and read through every page of this thread. I have not seen Bob's actual opinion on the performance of this gyro. If someone has seen it, if you point it out, I would appreciate it. If he hasn't given one, I would appreciate hearing your (Bob's) official opinion about the performance of this gyro. I was thinking about upgrading from my 401, because this inconsistent piro rate (especially in windy conditions) is starting to bug me. As always, thank you Bob for all your work and putting up with all (us) newbies. I couldn't have successfully gotten started on my own without your vids and the help of all the HF members. __________________ 8S Trex 500 ESP

01-31-2009, 07:19 AM	#231 (permalink)
TheBum HF Support My HF Map location Join Date: Jul 2007	The one weakness it has IMO is the brutally abrupt stops at the end of piros. Some people have actually reported stripping torque tube gears from it stopping so fast. It's nothing that can't be overcome by changing the way you stop your piros, i.e. easing your way that last little bit to center stick. It holds rock solid in a hover. When I was breaking in the engine on my T-Rex 600N, the tail held steady even with a brisk crosswind. The piro rates have been consistent left and right, certainly much more so than the 401 on my Diablo. __________________ Alan (just call me "Bum"; no need to be so formal) HeliFreak Support Protos Max Evo 700 (Brain 2), Protos Max V2 770 (iKON 2), Synergy 516 (Brain 2), Oxy 2 (Falcon 12) Graupner MZ-32 Experience is something you gain only after you need it. I wouldn't mind social media so much if it didn't involve people.

12-07-2008, 05:30 PM	#221 (permalink)
ayash Registered Users Join Date: Jul 2008	Looking into various web sites looking for a good deal on G770 I noticed there are two packages labeled as G770T and G7703D. See below a question (unanswered) with photos of the two http://www.runryder.com/helicopter/t380119p1/ Can anyone explain the difference? Is it the same only in a different package? Or two different gyros?

01-05-2009, 01:04 AM	#224 (permalink)
heliaddict22 Registered Users Join Date: Jan 2008	is this a good gyro? would you put it in T-REX 250?

01-05-2009, 10:55 AM	#226 (permalink)
Kratos Join Date: Sep 2008	First of all, thank you for the videos, very, very helpful. It's allways better to see what's going on. I have the 7703D on my 450SE and, with your help, have been able to finally get it set to where it is back in flying order. I just got the Align 500E scale fuse for it. I am going to have to remount the servo (S9650) from the side to straight under the boom to get it to fit and possibly install a new control rod (came with fuse). Any imput, or will I just need to fly and try? I know that this gyro is pickey and also likes a certain control rod length. Any insight, sugestions or ideas will be apreciated. Thanks

01-12-2009, 05:35 AM	#228 (permalink)
mr wokka Registered Users Join Date: Apr 2005	Hi Bob great vids by the way do you use Expo on the JR770 as i have piro rate set through Dual rates some say you should dial in 40% Expo true or not thanks Dave.........

01-31-2009, 07:34 AM	#232 (permalink)
Pinecone Registered Users Join Date: Sep 2006	More expo. Remember the 770 3D doesn't have ANY interanl expo. So 40% expo is like 0% on other gyros. You want to use 50 - 60% expo with this gyro. __________________ Terry AMA#47402, IRCHA # 3395 Blade CP "Pro", Trex 450SE, PiccoZ, Quick of Japan EP8v2 EX, Hurricane 550, Hurricane 200, JR Vibe 50, Blade mCX, Bergen Intrepid Gasser, Pantera 50, Blade mSR, Novus CP

02-02-2009, 01:24 PM	#234 (permalink)
Finless Team Taco VP Thread Starter My HF Map location Join Date: Nov 2005	Well comparing the Spartan to the JR770 is an apples to oranges comparison! The Spartan has far more adjustments and features and can be tweaked more to a certain pilots liking.... If the price of these 2 gyros was the same, I would go with the Spartan any day. Bob __________________ "Don't Taco My Pack Dude!" NEW Video Link -> Safety Video #1 Video Link -> CAUTION using powerful tools! Video Link -> How to CRASH TWICE in one flight! Video Link -> Don't Taco!

02-11-2009, 07:26 AM	#235 (permalink)
Hercman Registered Users Join Date: Aug 2008	JR770 Set-Up Issues First I must say I have found Finless Bob's how to videos amazing. They have been instrumental in learning all about my TREX 450.....as a "planker" I had some knowledge of R/C toys however very little on helos and setup. Thanks Bob! My issue and question is related to setting up a JR 770 gyro on a TREX 450 with a JR XP7202 radio. I have set up the gyro according to the instructions and Bob's tutorials. The gain lead is on my GEAR channel and I am using gear travel adjustment to set it. When I have the travel adjustments both + and -set to 0%, the tail servo moves left and right coming back to center each time when the stick is centered. If I add some gain on the + side (have tried 30-60% on travel adjust), moving the rudder stick causes the servo and tail rotor to move and just as in the videos, it will not completely return to center since there is gain set in the travel adjust. My problem is that when I move the tail left and right, the gyro is not sensing tail movement and NOT compensating by feeding in tail rotor pitch. I have tried everything I can think of and am still stuck All else appears to be operating as it should and the gyro and servo (JR3500) are both brand new. Can anyone help me out troubleshooting this one? Iwould appreciate any suggestions on this matter. I am convinced it is a setup issue but don't know enough to sort the problem out.

02-12-2009, 02:27 PM	#236 (permalink)
Empot Registered Users Join Date: Mar 2007	I was using this gyro initially with a S9254 servo and I was getting some wag when turning but none in hard 3d. I upgraded to a 8900G servo and I never looked back since. I dont have problems with it even on fast piro's my expo is 50 and my gain on dx7 is 63 on gyro menu using KBDD blades. I find it its better with KBDD than the stock CF blades. backwards flight really holds well even when I try to push it really hard. Im very happy with it. __________________ Thanks, Edward

02-17-2009, 09:31 PM	#238 (permalink)
Redfire SVT Registered Users Join Date: May 2008	Just in case someone needs to print off the manual: http://www.jrradios.com/ProdInfo/Fil...structions.pdf

02-18-2009, 09:40 PM	#239 (permalink)
Redfire SVT Registered Users Join Date: May 2008	Half way down page the 770 is setup for a Trex 500. http://madcow-productions.com/mluciaheli/?p=22

03-21-2009, 08:32 PM	#240 (permalink)
povern Registered Users My HF Map location Join Date: Apr 2008	Double Checking Formulas So I watched the Gain 101 video, and the formula given for finding true gain using end points is: endpoint / 1.44 = true Gain But when I watch the video, when Bob sets the end point at 150, the gyro reads 113 and in another spot when the endpoint is 32, the gyro reads 25 The formula used to match these numbers is: endpoint / 1.33 What am I doing wrong? Just want to know what the gain is that I'm currently running before I go to the gyro menu, and start setting up my 7703d. povern __________________ Screw It, I'm gonna fly. VControl, Neo, Hobbywing, Goblin 570(s)

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