not enough experience, or none at all!

[jhettel]

not exnough experience

Reg: Thanks for all the help.

I checked everything again and still have no results. I tried removing C11 and that did not help. Also my C1 is 100 uf as called for in the list of parts and it is installed correctly as are the diodes. As of yet I have not installed any of the transistors. Now for the readings I am getting on IC1 and IC5 are as follows: IC1 pin 1. 0; pin 2. -11.18 (I have a weak battery); pin 3. -11.70; pin 4. -.01; pin 5. -11.16; pin 6. -10.96; pin 7. -9.32-36 (jumps between .32 and .36); pin 8. 0.
IC5 pin 1. -4.92; pin 2. -2.38; pin 3. -.36; pin 4. 0; pin 5. -1.63; pin 6. -2.38; pin 7. -2.38; pin 8. 0

IC1 is definately a 7660 and there are no solder bridges. I used IC sockets and checked all of the pins on the sockets after they were soldered to make sure there were no bridges. All of the IC's are installed in the correct direction also.

Thanks for the help

[Pilot68]

Two types of ICL7660 !

Hi,

looks like IC1 isn't working. Be sure of using the right version of ICL7660, only the one with an "A" in the suffix (ICL7660A...) is operating with 12V. Other types only with 5V! Maybe that's the problem.

Also possible is a wrong direction of C4, which may cause a shortened voltage at IC2 Pin 3, but i think you've checked this already.

Jörg

[Carl-NC]

IC1 might be bad, but I'm going to guess that you have a solder short either across C4 or between pins 2 & 3 of IC2.

[jhettel]

I checked the 7660 and it is marked ICL7660. Beneath that is CPA. and beneath that is marked iS8806. I rechecked C4 and it is installed correctly in regards to polarity. Thanks

[Carl-NC]

Use an ohmmeter on a medium range (10k-20k) and measure the resistance across C4, with power disconnected of course.

[jhettel]

Carl: I checked both C4 and IC2 with my meter and there are no shorts in either one. I will get out my magnifying glass and check out every solder joint on the board and also check with my meter and get back with you.

[Carl-NC]

OK, I know this is getting tedius... pull IC2 off the board. Power up, and measure the voltage across C4. If it is still 0v, then IC1 is likely bad. Replace with a 12v version.

[jhettel]

Thanks Car. It is not getting tedious because of all the help you guys are giving me. I pulled IC2 off the board and will replace it with a 12v. version either way. Thanks

[Carl-NC]

IC2 is the 3-pin regulator... if you've pulled it off, power up & measure the voltage across C4. It should be around +12V. If it is, then IC2 is bad. If it is still ~0V, then IC1 is bad.

[jhettel]

I have just returned from the electronics store where I purchased new ICL7660 and 78L05 IC's. Should I go ahead and install these IC's at this time or should I do any more tests to make sure that I do not blow these two IC's also. Can I compare the pins of the old and new IC's with a multimeter to see if there are any differences at each pin, that may tell me if the original IC is bad or not.

[jhettel]

not exnough experience

I was just about to give up when I discovered that a battery wire had came loose and when I soldered it back on I soldered it in the wrong place. I changed the connection and was able to get all of the correct voltages (both + and -) from all of the IC's that I have been struggling with. I have since installed all of the components for the clocking circuitry and am presently working on the transmit circuitry and preamp. I have everything but the diodes and Q1 and Q2 installed. Hopefully I can get through this next portion and complete the circuit board and start on the coil. Thanks

[jhettel]

I have been struggling along and have decided to put the project on hold for a few months. I do have the board about halfway finished but cannot get some of the voltages correct and the 100 mile round trip to the electronics outlet is getting kind of tiring. Just wanted to thank Reg and Carl for their help.

[Carl-NC]

Send it to me if you want.

[jhettel]

Carl, you are a great guy and a great administrator. I really appreciate the offer. I am not sure what went wrong with my board. The local electronics store said they could supply all of the parts, which they did, but I am not sure that what they supplied and what they had in stock was really what was needed for the project. They told me that it really didn't make much difference on some of the parts. I know that either one of the transistors or one of the IC's was a similar match, but not exactly what was called for in the instructions. I cannot get to the project for a few weeks because I will be going out of town for the next few weekends on reenactments, that I am involved in, and, this is the season. Let me get through the reenactment season and then I will go back and get a few more parts and change them out and see if I can get the correct voltages. I would really like to get the Hammerhead working as I know that it would be a great machine to use and would probably enable me to go down and get the big ones (artillery shells from the civil war near New Madrid, Mo.)

[ManBearPig]

Hi guys, this is my first post on geotech, until now i've just been reading up on all i can here about the HH before i ask a potentially obvious question, however my first post was going to be similar to this one (other than quitting, i'm too damn stubborn for that haha ). I'm building the HHd kit from Silverdog -thanks for very quick service from him!, and the ground leads on my multimeter were round the wrong way - had red to pos on power connection and started to wonder if maybe they were wrong way round or if i'd installed something wrong with same voltages measured as jhettel, but was unsure due to positive gnd and found my answer here thanks to advice from Carl and reg. I just wanted to say how nice it was to see how jhettel wasn't ridiculed for inexperience like most places on the internet, and instead was given such friendly generous advice from Carl and reg including an offer from Carl to personally look at it! This advice was helpful to me, and felt it was appropriate to say thanks to Carl and reg on behalf of those of us who are still learning and do this as a hobby and got something out of this thread, and thanks to jhettal for posting the question - i dont feel so silly about my mistake now, and i learned something. Now i can move on to the next step!! Cheers guys, awesome forum you have here and hope to have pictures of complete detector to post soon!