Go Back   RCCrawler Forums > RCCrawler General Tech > Electronics
Loading

Notices

Thread: 6ch Pistol Tx - a cheap alternative?

Reply
 
LinkBack Thread Tools Display Modes
Old 07-31-2009, 07:33 PM   #61
RCC Addict
 
Join Date: Oct 2008
Location: Plainfield, IL.
Posts: 1,297
Default

Quote:
Originally Posted by clockworks View Post
Yes. If you get a "mode 1" Tx, it comes with a ratchet throttle on the right stick. A "mode 2" Tx comes with a ratchet throttle on the left stick. You can swap the parts around if you want.

The throttle pot is identical, whatever mode Tx you get, just the mechanical parts are different. A plane throttle stick works fine as a car throtttle stick if you swap the ratchet for a spring.

Because a plane ESC only goes forward, you use the full range of the stick for forward. A car/truck ESC has forward and reverse, so you use half of the throttle travel for each. The neutral, forward and reverse points are set when you program the ESC.

Your best bet is to buy a "mode 1" Turborix. It'll come with a spring on the left stick up/down, so you can use it as the throttle for your crawler. If you can only find a "mode 2" Turborix, you'll have to swap the ratchet and spring around.
I was looking at this one, its the only one i can find in stock anywhere.

http://www.hobbycity.com/hobbycity/s...x_&_Rx_(Mode_1)

Think this one will have a spring on the left stick for throttle?
InFlames is offline   Reply With Quote
Sponsored Links
Old 08-01-2009, 12:53 AM   #62
Rock Crawler
 
Join Date: Feb 2008
Location: UK
Posts: 818
Default

Quote:
Originally Posted by InFlames View Post
I was looking at this one, its the only one i can find in stock anywhere.

http://www.hobbycity.com/hobbycity/s...x_&_Rx_(Mode_1)

Think this one will have a spring on the left stick for throttle?
Yes, that's the one you need. It'll have a sprung left stick.
clockworks is offline   Reply With Quote
Old 08-01-2009, 07:10 AM   #63
Pebble Pounder
 
Join Date: Jul 2009
Location: Windsor, UK
Posts: 141
Default

that rotary switch sounds perfect. Add in a few 3 or 2 way switches and you'll have a radio that IMO someone should release as a crawler radio.

Any idea if you're going to do momentary 3-pos switch or normal one? I suppose for a winch a momentary one would be best, but for a dig you'd want one that stays where set. Perhaps have one of each, and the 3-pos 'normal' switch could also be used as a 2-way if preferred (for lights etc)
mrklaw is offline   Reply With Quote
Old 08-01-2009, 07:46 AM   #64
Rock Crawler
 
Join Date: Feb 2008
Location: UK
Posts: 818
Default

Quote:
Originally Posted by mrklaw View Post
that rotary switch sounds perfect. Add in a few 3 or 2 way switches and you'll have a radio that IMO someone should release as a crawler radio.

Any idea if you're going to do momentary 3-pos switch or normal one? I suppose for a winch a momentary one would be best, but for a dig you'd want one that stays where set. Perhaps have one of each, and the 3-pos 'normal' switch could also be used as a 2-way if preferred (for lights etc)
Here's a photo of the wiring list for the rotary switch. A schematic would probably be unreadable, given my poor drawing skills:

I've followed the wiring colours of the original Turborix Tx where appropriate.


I've had a closer look at the "spare" channels. The elevator channel (ch2 on my Tx) and channels 5 and 6 can all be converted, as 5 and 6 use standard 5K pots, same as the stick channels.
This leaves us with 5 or 6 channels to configure any way that's needed for a particular crawler.

If you have 4ws, you can use the rotary switch, leaving 2 channels for 2- or 3-position switches.
If you have dual ESCs, you'd probably use a 3-position rotary switch and have three 2- or 3-position switches
If you only have a 2ws crawler, you can have four 2- or 3-position switches.

The reason why 4ws has less channels is because you need 2 of the 3 mixes to make the steering work, meaning that you can't use both chs 5 and 6.

I actually have no use for a 3-position switch, I'm doing this purely for fun, although I'll probably add the rotary switch to my original DX6i/Mars conversion. The Tx might be available when I've finished, if none of the local crawlers want it.
I think that I'll build it with one of each type - latching and momentary.

I agree that it'd be nice if someone made these for sale, although I doubt that there's much demand here in the UK. I'm working full time, plus I'm running my own small business, so I don't really have the time to do this. A one-off maybe, but not in any kind of volume.
clockworks is offline   Reply With Quote
Old 08-01-2009, 08:07 AM   #65
Rock Crawler
 
Join Date: Feb 2008
Location: UK
Posts: 818
Default

3-position switch mod has been tested. Here's the schematic:



And the test rig:



This is the "full house" mod, allowing easy adjustment of the centre point (left pot in drawing and in photo) and both end points. This could be useful on a cheap programmable Tx like the Turborix, and is definitely useful on a non-computer Tx.

If you want the trim and EPA adjustments easy to operate whilst driving, use proper pots. If you want to hide them away, use trimmers.

With this setup, the trim range (centre position adjustment) is adjustable over the entire travel of the servo. The endpoint adjustment (switch in either of the "on" positions) range is from about 25% to 150%.
This adjustment range should cover all real-life applications.

I fitted this on ch2 (right stick up/down). I removed the 3 wires from the pot and soldered them to the 3 wires coming in at the left of the pic. The colours match those on ch2.
The same mod will work on ch5 or 6, but the centre wire colour is different.

The pot or trimmer values aren't set in stone - use something close, whatever you can get your hands on. Don't go too low, though.
clockworks is offline   Reply With Quote
Old 08-01-2009, 08:41 AM   #66
Pebble Pounder
 
Join Date: Feb 2009
Location: LeMars, Iowa
Posts: 158
Default

You guys will have to forgive me, but I just finished up my $50 ghetto 6ch tx,
and felt the giddy school girl need to post something about it.

I know this thread has progressed much farther tech-wise than what I've been working on the last couple of nights, but here goes.

Of course, like all projects, it's not finished:

No, it's not a bad photoshop job, it just looks like it!











It's pretty rough, but then again, I've only got about $50 total invested.
Until I can find a better solution, I'm running ch 2 & 5 mixed for throttle control. The goal is the have the ability to run ch 1 & 4 , and ch 2 & 5 mixed or stand alone at the flip of a switch (just ran out of time the other night, and wanted to test it before I went any farther).
WarMachine is offline   Reply With Quote
Old 08-01-2009, 08:50 AM   #67
Suck it up!
 
Duuuuuuuude's Avatar
 
Join Date: Mar 2008
Location: Arkansas
Posts: 11,652
Default

Holy hell, that thing is an abomination!






Let us know how it works!
Duuuuuuuude is offline   Reply With Quote
Old 08-01-2009, 09:02 AM   #68
Pebble Pounder
 
Join Date: Feb 2009
Location: LeMars, Iowa
Posts: 158
Default

Quote:
Originally Posted by Duuuuuuuude View Post
Holy hell, that thing is an abomination!
Let us know how it works!
It definitely is...but it's oddly well balanced and somewhat comfortable. It's going to take some getting used to...but what the hell, it was fun.

Last edited by WarMachine; 08-01-2009 at 10:56 AM.
WarMachine is offline   Reply With Quote
Old 08-01-2009, 09:49 AM   #69
Rock Crawler
 
Join Date: Feb 2008
Location: UK
Posts: 818
Default

Certainly the most unusual conversion that I've seen!

Exactly what have you done, and how are the controls set up?
I presume that you are using 2 Tx PCBs and 2 Rxs, but are you using both wheels? What about the triggers - 2 pots, or one pot feeding both PCBs?
Are you using 16 AA cells?
clockworks is offline   Reply With Quote
Old 08-01-2009, 10:55 AM   #70
Pebble Pounder
 
Join Date: Feb 2009
Location: LeMars, Iowa
Posts: 158
Default

Quote:
Originally Posted by clockworks View Post
Certainly the most unusual conversion that I've seen!
Exactly what have you done, and how are the controls set up?
I presume that you are using 2 Tx PCBs and 2 Rxs, but are you using both wheels? What about the triggers - 2 pots, or one pot feeding both PCBs?
Are you using 16 AA cells?

Pretty much spot on with what I did.

2 tx pcbs, and 2 rx.
Channels 1,2,3 on tx/rx 1.
Channels 4,5,6 on tx/rx 2.

Tx1 trim on the right side
Tx2 trim on the left side
Ch 1: Right side wheel (front steering)
Ch 4: Left side wheel (rear steering)
Ch 2 & 5: Throttle via one pot (one or two esc)
Ch 3: Thumb momentary set (dig unit)
Ch 6: Finger tip momentary set (laser death ray gun)

Eventually if I can find a suitable pot for the "mixed" throttles I'll separate them, but I haven't added the toggle switches for solo/mixed 2&5 yet. Just plain out got in a hurry to try it.

Running it all off the 8 AA's in the bottom.

The scope of this project (code name: Super Secret Project 6) was to make a useable 4 ch out of what I had laying around on the bench. The added bonus of 2 more channels opens up other possibilities down the road....or I'll shelf it and move on to Super Secret Project 7 (a whole different take on a controllers and CHEAP)

WarMachine is offline   Reply With Quote
Old 08-01-2009, 12:26 PM   #71
Pebble Pounder
 
Join Date: Aug 2008
Location: Spain
Posts: 103
Default

Quote:
Originally Posted by clockworks View Post
3-position switch mod has been tested. Here's the schematic:



And the test rig:



This is the "full house" mod, allowing easy adjustment of the centre point (left pot in drawing and in photo) and both end points. This could be useful on a cheap programmable Tx like the Turborix, and is definitely useful on a non-computer Tx.

If you want the trim and EPA adjustments easy to operate whilst driving, use proper pots. If you want to hide them away, use trimmers.

With this setup, the trim range (centre position adjustment) is adjustable over the entire travel of the servo. The endpoint adjustment (switch in either of the "on" positions) range is from about 25% to 150%.
This adjustment range should cover all real-life applications.

I fitted this on ch2 (right stick up/down). I removed the 3 wires from the pot and soldered them to the 3 wires coming in at the left of the pic. The colours match those on ch2.
The same mod will work on ch5 or 6, but the centre wire colour is different.

The pot or trimmer values aren't set in stone - use something close, whatever you can get your hands on. Don't go too low, though.
Hi Steve, I use 1k EPA pots. They can subtract about 25% of final range.
meao is offline   Reply With Quote
Old 08-01-2009, 12:41 PM   #72
Rock Crawler
 
Join Date: Feb 2008
Location: UK
Posts: 818
Default

Quote:
Originally Posted by meao View Post
Hi Steve, I use 1k EPA pots. They can subtract about 25% of final range.
Yes, a smaller EPA pot will give less adjustment range, but finer/more precise control. A smaller pot like you use is probably better for adjusting in the field, as the basic adjustment can be done using the software.

I need to find some miniature pots and suitable knobs.
Are the trims in the HSP Tx suitable for re-use in the conversion?

I've been googling for info on fitting a 3s LiPo. Most people say the Tx is fine with the slightly higher voltage. Once the HSP Tx arrives, I'll try and find a LiPo that fits.
clockworks is offline   Reply With Quote
Old 08-01-2009, 02:30 PM   #73
Pebble Pounder
 
Join Date: Aug 2008
Location: Spain
Posts: 103
Default

Quote:
Originally Posted by clockworks View Post
I need to find some miniature pots and suitable knobs.
Are the trims in the HSP Tx suitable for re-use in the conversion?

I've been googling for info on fitting a 3s LiPo. Most people say the Tx is fine with the slightly higher voltage. Once the HSP Tx arrives, I'll try and find a LiPo that fits.
I haven`t try them. Later, when I came back home I`ll tell you the resistance value. They are board pots.

I`ve find a mod to use only 4cells!!!. They say about 10hours working and no range trouble. IŽve troubles to understand correctly how to make the mod so I cannot try it. Later iŽll give you the link.
They also say, that sometimes the PCB`s voltage regulator(7805) is not as good as must, so with this mod, the trouble is corrected.

Cheers.
meao is offline   Reply With Quote
Old 08-01-2009, 03:59 PM   #74
Pebble Pounder
 
Join Date: Aug 2008
Location: Spain
Posts: 103
Default

Quote:
Originally Posted by meao View Post
I`ve find a mod to use only 4cells!!!
Links:

Post #783:
http://www.rcgroups.com/forums/showt...967207&page=53

Post #1286:
http://www.rcgroups.com/forums/showt...967207&page=86

Cheers
meao is offline   Reply With Quote
Old 08-01-2009, 05:14 PM   #75
Rock Crawler
 
Join Date: Feb 2008
Location: UK
Posts: 818
Default

If I understand it correctly, the Tx takes the input from the 8 AA cells (between 9.6v and 12.8v, depending on the type of cell and the state of charge) and uses two 5v regulators to drop the voltage.

The mod converts the battery box to use 4 cells, supplying between 4.8v and 6.4v. The two regulators are disabled by shorting the input to the output.
The circuits now run directly on the battery voltage.

There appear to be 2 versions of the mod. One bypasses each regulator individually. The other bypasses one regulator, then feeds it's output (which is shorted to it's input) to the output of the other regulator.

The LED appears to alter the sensitivity of the low-voltage warning LED.

If I had a spare Tx, I'd try this mod. I'm wary of risking my only Tx.
clockworks is offline   Reply With Quote
Old 08-01-2009, 05:49 PM   #76
Pebble Pounder
 
Join Date: Aug 2008
Location: Spain
Posts: 103
Default

Quote:
Originally Posted by clockworks View Post
There appear to be 2 versions of the mod. One bypasses each regulator individually. The other bypasses one regulator, then feeds it's output (which is shorted to it's input) to the output of the other regulator.
OK, THANKS STEVE!!!!, now I understand it perfectly

I've a couple of TX here waiting for building to pistol, so I'm going to try it. If it works would be wonderful!.

Cheers
meao is offline   Reply With Quote
Old 08-01-2009, 05:57 PM   #77
Rock Crawler
 
Join Date: Feb 2008
Location: UK
Posts: 818
Default

Quote:
Originally Posted by meao View Post
OK, THANKS STEVE!!!!, now I understand it perfectly

I've a couple of TX here waiting for building to pistol, so I'm going to try it. If it works would be wonderful!.

Cheers
Excellent!
clockworks is offline   Reply With Quote
Old 08-01-2009, 06:22 PM   #78
Pebble Pounder
 
Join Date: Aug 2008
Location: Spain
Posts: 103
Default

WORKING!!!!

Uploading pics & vid.............
meao is offline   Reply With Quote
Old 08-01-2009, 06:39 PM   #79
Pebble Pounder
 
Join Date: Aug 2008
Location: Spain
Posts: 103
Default

Pics of voltage regulators bypassed:





Batery box modified to solder the positive wire properly:



And the vid of TX working after the Mod:

http://www.youtube.com/watch?v=rmBsZzEZnnM

I'm very happy!
meao is offline   Reply With Quote
Old 08-02-2009, 01:11 AM   #80
Rock Crawler
 
Join Date: Feb 2008
Location: UK
Posts: 818
Default

Great. Are you going to try adding the LED as well?
Also, what type of cells did you use - I wonder if it works with cheap NiMH?
clockworks is offline   Reply With Quote
Reply



LinkBacks (?)
LinkBack to this Thread: http://www.rccrawler.com/forum/electronics/190457-6ch-pistol-tx-cheap-alternative.html
Posted By For Type Date
ZONACRAWLING • Ver Tema - -CRAWLECTRONICS- "Post Oficial" This thread Refback 02-19-2013 05:12 PM

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -6. The time now is 08:51 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO ©2011, Crawlability, Inc.
Copyright 2004-2014 RCCrawler.com