Modified Harbor Freight Pinpointer w/ pics

The motor adds the abilitiy to feel an alert. Helpful when wearing headphones. Just like having your cellphone on vibrate. Disabling the speaker allows for stealth mode when others are nearby.
 
got mine a little modded up today
been needing a PP and dont have the cash for a new Garrett so had the old Harbor Freight PP laying around but like most the power button was bad. so off to radio shack i went today.
picked up a button but they didnt have any viberating motors. so got home and got the button put in and all of it worked well speaker still works also but with headphones sometimes it can be tough to hear the speaker.
so what i did was i tied in 2 wires with the wires on the speaker, i removed the led terminals from the circut board and tied the led to the speaker. now when it sounds off the led lights up as well.
when radio shack gets in one of the motors im going to work on putting it in as well
so far its working well and hopefully will suit me for quite a while.
 
Does anyone have one of the thermistors that is talked about on this thread,you might want to sell?
Does anybody have picture of the thermistor soldered on the board?
 
got mine a little modded up today
been needing a PP and dont have the cash for a new Garrett so had the old Harbor Freight PP laying around but like most the power button was bad. so off to radio shack i went today.
picked up a button but they didnt have any viberating motors. so got home and got the button put in and all of it worked well speaker still works also but with headphones sometimes it can be tough to hear the speaker.
so what i did was i tied in 2 wires with the wires on the speaker, i removed the led terminals from the circut board and tied the led to the speaker. now when it sounds off the led lights up as well.
when radio shack gets in one of the motors im going to work on putting it in as well
so far its working well and hopefully will suit me for quite a while.
I've never had to replace the button on mine yet..but I have had to clean it a couple of times... one tip that will help with the button is .. you can remove the switch, then cut a finger tip off of a latex glove and cover the switch the reinstall the switch.. this will keep dirt from entering the switch and damaging it..
 
I've never had to replace the button on mine yet..but I have had to clean it a couple of times... one tip that will help with the button is .. you can remove the switch, then cut a finger tip off of a latex glove and cover the switch the reinstall the switch.. this will keep dirt from entering the switch and damaging it..

Excellent idea, I'll do that to mine.
 
my cen-tech~

i replaced button witha forklift seat preasure switch, and installed a vibrator motor from a cell phone.....works great its my first and only pinpointer ive used (to give you an idea on longevity) vibrates and lights up still after all these years. and my motor is wired directly to the power for the led lights( no resistors used) and the forklift seat switch is waterproof and very tough.~~
 

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almost forgot.....

the adjustment dail..... i put a plastic washer down over the knob then used a black rubber vacum cap (automotive) pressed down against the washer to keep out moisture and dust... works awsome!!
 

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i replaced button witha forklift seat preasure switch, and installed a vibrator motor from a cell phone.....works great its my first and only pinpointer ive used (to give you an idea on longevity) vibrates and lights up still after all these years. and my motor is wired directly to the power for the led lights( no resistors used) and the forklift seat switch is waterproof and very tough.~~

I think the clover stickers are the best mod! :D
 
Gain ~1/4" mod.

Remove the end cap buy getting a thin blade and slowly prying upwards going all the way around. Eventually it will come off.

Once off, you will see about a 1/4" gap (could be more, depends on where it was set) from the end of the rod inside to the end of the pvc.

Measure the depth and mark it along the outside of the pvc. Trim it down with a saw to where the rod is now flush with the pvc. Now trim the cap the same amount (it is plenty long), remove the craft glue from inside then put it back on.

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I've modded 2 of these already with vibrate motors and new switches. Just spend the money and get a real one...These really dont hold a candle to my garrett at pin pointer. I save the cheap ones for friends.
 
I agree that the HF doesn't compare to the carrot but it's a lo0t better than the hand to coil method of sorting through a plug. I modded mine with the switch change, vibrating motor, tip protector, larger sensitivity knob and moved the speaker into the wand opening to quiet it down. It'll be a back up for sure now that I own a carrot and if some one else comes along that wants to try the sport it will cut down on their search time. It's a good cheap way to begin in my opinion.
 
Here is my humble pointer. All I've done for "performance" is adjusted the screw inside. I put a clip from a Tape measurer since I wasn't happy with how the pouch that came with it fit and removed the decals. I didn't want it to look like a gun hanging on my belt or pocket so I painted it red with some plastidip I had laying around the house.


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I added a vibrating motor to mine since i can't hear it anyway. Once I saw some boys throwing rocks at cars on the turnpike from where they were hiding in some bushes. They saw me but I was pretty far away so I acted like my HF pinpointer was a mobile radio. The must have thought that I was calling the police because they got scared and ran away. I should have had my phone with me but the pinpointer worked.
 
I found this info on another forum, thought I'd share.:newidea:

"Modded the Centech 97245 detector as follows:

1. Moved the ground end of the LED to the output of the 2N7000 FET - Originally the LED was lit when ever the power was on AKA a Flashlight. This mod makes the LED a signal strength indicator and a threshold setting indicator as it is only on when threshold is set too sensitive or a target is detected.

2. Doubled the piezo limit resistor to 150 ohms - reduces power consumption and makes the piezo more bearable.

3. Added a pager vibrator motor and a 180 ohm limit resistor in series. Provides tactile feedback and silent operation around others.

4. Installed a DPDT select switch controlling 'Vibrate' or 'Audible' indication of detection.

5. Installed a 100 ohm thermistor to help with stability.

6. Installed a .22uf cap to filter out ripple on the comparator input.

7. Reset internal range pot in the Sensitivity control part of the circuit to allow proper range of the external Sensitivity pot.

8. Replaced the TL062 dual op amp with a TL082 dual op amp. Improved stability.

The detector now gives varying audio tone going low when a target is detected and target detection is always accompanied with brilliant LED light. The light is a great help in presetting threshold for more depth as you can set for very low illumination of the LED in the idle state.

Note: The original board comes etched, drilled, and marked for most of these component changes but they were left out in manufacture presumably to cut cost.

The jury is still out on the sliding ring trick originally posted elsewhere in the Tech Forum. I think it works on detectors that have not been optimized with mods. It does this by mechanically bringing the detector closer to its sensitivity threshold. The sliding ring may have a benefit in reshaping the field around the ferrite rod but I have not yet been able to prove this to be true. If it does then it may still be worthwhile.

Detection distance of this detector on a 1/4" X 1/4" piece of aluminum can is now 0.75". US Nickle is 2.375"

The most sensitive area of the search probe is the first 1.5" from the tip.

This modified pinpointer really speeds up target recovery. "
 
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