I recently bought an old heath kit gd-1190 detector off feebay---well guess what when I received it "no workee"---does anyone repair these old detectors, besides keith wills--also would like to hear from anyone tha may have used one--is it worth repairing??????
Only HeathKit I ever used was a HeathKit 348 that I built myself. It was a good detector, not the best, But it worked satisfactorily. Don't know anything about the rest of them. I have no idea if they are worth fixing or not. Good luck finding out!
Challenger X-70, Challenger X-80, Challenger X-90, Challenger X-100, Challenger X-200, Coin Scanner Pro II, Judge 2 Auto
I am going to stick my neck out...and ask if you're the same 'CLARK' who has been a treasure hunter for over 50 years? If not,then forgive me. Welcome to the Compass and other assorted metal detector forum. Keith Wills is the only person I know that repairs the older metal detectors.
THAT'S ME----I'VE BEEN DETECTING SINCE ABOUT 1955 ---GOOD OLD DAYS---I'VE ALWAYS PREFERED THE OLDER METAL DETECTORS, TO THE NEWER ONES---TO ME, THE NEWER DETECTORS ARE GREAT FOR CLAD COINS--I'VE TRIED THEM ALL, ALWAYS GO BACK TO THE OLDER ONES, EVEN IF THE OLDER DETECTORS ARE "SLOWER", I'M SLOWER ANYWAY BECAUSE OF MY AGE AND HEALTH--TO ME THE NEW DETECTORS " WILL NEVER COMPARE TO THE OLDER ONES IN THE QUALITY OF YOUR FINDS"---IN OTHER WORDS, " I WOULD RATHER COME HOME WITH (1) OLD COIN, EVEN IF IT WAS AN OLD INDIAN PENNY, THAN A POCKET FULL OF CLADS !"
I don't know much about electronics-- I looked it over for loose wires or bad solder points, but my eyesight is not that good anymore---I replaced the battery plug but that didn't seem to help--I heard years ago that the old heath kit detectors were of the " off resonance design"--don't know if that's true or not--always wanted to try one--I ran into a guy years ago that was using a heath kit detector and he was digging old coins everywhere--he would guess what the target was before he dug it up, and 95% of the time he was correct--he could tell by the sound--I had a whites 6000 di and he beat the heck out of me--if I recall correctly,at the end of the day he had (8) barber dimes,to my (1)--nothing was really deep,but the whites was no comparison to the heath kit ????
you seem to know a lot about electronics, could you repair my detector--I would gladly pay a reasonable price?????--- plus you and I and the rest of the forum guys could all see " first hand" if this old heath kit is really that good or not ! --we are all, always looking for that " little sleeper " detector that no-one else knows about !
I was just looking at the 1190 schematic, The 1290 is a more typical detector but this 1190 is odd in the way it only has a single coil winding . It is still a fairly simple circuit and I can see how it works. What is the detector doing or not doing, any sound at all. I would be sure to try cleaning the rotary switch. Looks like it could be a problem area if it has been sitting. If that does not do it then I could probably work on it for you. It is very straight forward and I could scope out the problem in no time. I bet this detector has a lot of drift with the single winding coil. It would be interesting to find out. But in all honesty I doubt that this design works very well. I must say this is a novel design that I have only seen once before on a foreign schematic.
What state are you in ? Anywhere near Texas?
....Hi Clark...How about posting a Pic of your detector?? I had a HeathKit about 7 years back but at this time do not remember if it was the 1190 or the 1290??.....One of these is more like the VLF/TR models.......anyway also take some Pic's of the circuit board...we have some circuit board guru's that might be able to diagnose the problem!!..............I like reading your posts so do not be a stranger!!......Joe
thanks for the reply---I live in the NEW ORLEANS, LA. area---I sprayed the controls and it didn't help--when I turn the detector on battery check, the meter sometimes tries to work--but other times it does nothing--at no time can I get any sound from the speaker or headphones---one thing that I didn't try, was to check the wires from the battery--it looks like they may have been spliced at one time--I may try to replace the complete battery wires, with new ones????
I would also like to see a picture of this detector. I remember a Heathkit that sold for around $80. back in the 70's with the narrow case and handle molded together. The 1190 appears to operate on about 56KHZ. It looks like they use a TV color burst crystal in the oscillator and and divide it by 64. The detector is an off resonance type. It has no phase detector. When the coil is tuned to resonance the signal is at a maximum level. It looks like they probably tune it off to one side so a non ferrous target brings it closer to tune and increases the signal level. The disc. control on this detector is a pot that varies the voltage across a varactor diode that appears to fine tune the coil. There is not much to this detector at all. The detector operates on 5.5V after the regulator. You can check this at TP 1 on the bd. The audio is powered directly from the 9V battery at TP 3 on the bd. I can see that there should be a battery test tone when the detector is turned on.
It sounds like you are on the right track about the connection because when the switch is in the Batt test position it connects the positive side of the meter to the 9V battery connection at TP3 through cal pot R13. The negative side of the meter is connected to ground. This means that the meter circuit is looking across the battery and if it's not moving the most likely thing is a bad power connection to the bd.
The part of the circuit that I thought would create an audio tone at power up actually does just the opposite. It does not allow the detector to make any sound when you first turn it on until C12 charges. It keeps the detector from going nuts when you first power it on. Please hurry and send us some good news that you got it working. I am really curious now about how this detector performs. It is the most odd metal detector design that I have ever seen.
I redid the battery wires and plug, but still no sound---the meter moves about halfway when checked in the battery position of the switch--(that's about half of where the meter should move)--I can hear a chick sound in the speaker when I first turn the detector on, so I assume the power is going through the circuit,but after that click, then there is no sound whatsoever?????
The blue meter cal pot R13 is also in series with the meter so you can adjust the meter to the right spot with good batteries. The next step would be to check from test point 3 to ground with a volt meter and make sure you are getting 9 volts and nothing is loading the battery down. Then you need to check from test point 1 to ground and make sure you are getting the 5.5 volts. You can also check the audio and tone circuit by connecting a 1k ohm resistor or some value at least more than 100 ohms up to 1k from test point 1 to the junction were R14 and R15 are connected together. This should give you an audio tone. If this all works then you know the problem is back toward IC 2 and IC 1. If this does not work the problem is in the audio area. If you feel like this is becoming to much for you then send the detector to me and I will fix it for you at no charge. I can troubleshoot this detector faster with an oscilloscope than I can type these words. I have plenty of older components around here and there is not a a part in it that cost much more than 50 cents.
...Phase Shifter....I admire you....that is a great deed....One does not see that Kind of Generosity in this current age of ..........selfishish......My hat if Off to you...Wish we had/have more people like You......Thanks Joe
thanks--looks great---the problem with these detectors is trying to get them repaired--I have the model GD1190 which is the "off resonance" that I believe is the better model but can't get parts to repair it !