MEM-TEK modifications on ZR4

[niran916]

What ever happened to MEM-TEK?

he's been golfing.

[CJR238]

I read a copy of older threads on how MEM-TEK modified some ZR4s and improved their performance substantially. I own a ZR3 and have a degree in engineering so I am very handy with electronics and would like to make the same kind of mods.

Does anybody know if MEM-TEK disclosed his mods somewhere?

Before reading this I was considering making some mods of my own. I could use an JR45 splitter coming out of the control module and use that to drive a third head that I could make myself using some very powerful 904nm diodes I have around. This head would need it's own driving stage though, no biggie, just BJT to N channel MOSFET to diode should do it since the jamming algorithms are only running at about 100Hz. I would just need to find which wire does the firing coming from the control module.

Wont work, they need to be timed perfectly. The firing sequence isint just in the control module.

[RobInAlbany]

you sure about this? how do both of the transceivers know to fire at the same time? if they were independent wouldn't they have cross-talk?

To be sure I am going to try putting a scope on the output pins on the control module and look for the approximately 100pps firing. I will just need a way to get it to fire. I noticed that if you disconnect one of the heads while the power is on it sometimes alerts to laser.

[CJR238]

you sure about this? how do both of the transceivers know to fire at the same time? if they were independent wouldn't they have cross-talk?

To be sure I am going to try putting a scope on the output pins on the control module and look for the approximately 100pps firing. I will just need a way to get it to fire. I noticed that if you disconnect one of the heads while the power is on it sometimes alerts to laser.

Not shure if its the right or left head (left?) but one head is master and one is slave.

[roninmd]

I will just need a way to get it to fire

Use a tv remote and press the vol. http://www.youtube.com/watch?v=_oMig9E-pcA

If you come up with something, send me a schematic. I know you will need:
(8) 904/905nm laser diodes.
Better Optics.
a laser driver to drive your heads so that they don't burn out.

And beware that you don't look at the diode when it's active because even if you don't see the light it may cause retinal damage. Infrared is the radiant form of heat and when concentrated by your eyes lens, you have a bad situation in your eyes.

A simpler thing would be to replace the InfraRed LEDs with brighter InfraRed LEDs.

[RobInAlbany]

Thanks

Yea, replacing the diodes would definitely be easier, I wonder if that is what MEM-TEK. However, I don't know how much current the ZR3 amplifiers can supply. Some of these laser diodes can draw up to 1A! but thats peak current of course, because it is pulsed, otherwise the diode would burn out if it was continuous current. That's why I want to start from the ground up with an amplifier that can handle really high current. Here's an ultrasound amp I made awhile back:

http://static.ak.fbcdn.net/rsrc.php/...102431269&ev=0

Also, I really didn't want to open up my heads because I'm worried about breakin them. Ideally I want to just plug a splitter into the control molude and than have an extra head that I made coming out of that, using the original heads to sense the laser.

I bought a splitter last night and brought home a data acquisition unit from work so I record the exact signal that is coming out of the control module, and if there is indeed a pulse that I can use for my extra head that I'll make. But I am having trouble triggering it reliably with my remote, I have a curtis tv (sylvania subliterary) what is the one you use in the vid?

[roninmd]

Hey, that's some good work with the ultrasound device. The remote I used belongs to a 50 in LCD TV made by Vivitek.

If the heads are similar to the ZR4 heads. The tabs are easy enough to open the heads. Don't worry about the weather proofing it's designed in the housing. You shouldn't submerse them in water but they could handle rain.

Tell me what your findings are. I'm seriously interested in this mod stuff.

[roninmd]

Why don't you make this simpler. Create a separate head with your 904nm diode lasers array with proper power driver. Use some transistor relay to activate the laser head when one of the LEDs in the zr3 head is on.

What I'd like to do is find a way to get my head light to modulate with the zr4 firing. There's Lots of IR coming out of that headlight. Headlight modulation is legal in all 50 states because it's supposed to make motorcycling safer during the day. At night, the modulation must be turned off. What do you think will happen when the cop's photodiode detects the pulses of IR coming off the headlight.

[RobInAlbany]

good thought. however I would still need to trigger the zr3 to be sure that my head was reading it right. and then it would always be subjected to interference and noise from ambient light. using the pulse from the control module would be the most reliable method.

the headlights might not be able to flash that quickly. from what I am reading its between 100~200pps which isn't that fast but the pulses are only about 100nsec long. an incandescent light bulb has a much slower response time.

[roninmd]

To trigger the ZR3 have you tried making your own pulsed 904/905 nm laser to shine on the photodiode? The photodiode is on the outer side of the head.

From what I read about Mem-Teks mods. All he did was change the IR LEDs with Brighter LEDs and perhaps added a filter to the optic section to filter in the 905/905 wavelength specifically. Adding the filter; however, reduced the optic's sensitivity slightly.

He may have also changed the MOSFET that ran both front shifters.
When I spliced my front shifters with a phone coupler, I did not verify the orientation of the RJ11s so I blew out the MOSFET in the control module and a capacitor in the shifter head.

Luckily a family member was an engineer and replaced the components; however, he didn't have any MOSFETs available and wound up using another type of transistor.

Activating the shifters with tv remote and looking at the shifter heads through the Iphone clone camera, it seems the shifters are brighter. Before there was variability in brightness I must assume came from the field effects of the MOSFET. It's lost now with the new transistor installed which I must assume makes the LEDs just go on and off and not vary in brightness.

Before:


After:


I don't remember MEM-TEK making a laser diode array. These were much more simpler mods that anyone with a soldering iron and a bit of theory can experiment with.

Another must have MOD, is to add a diode in case a user crosses the wires when splicing the cables.