HAMMERHEAD REVISION D NEED ADVICE

[daverave]

i have the hammerhead revision D pcb....there are three holes in the pcb to select the type of mosfet drive...two of the holes has a little box marked on the pcb...which holes do i solder a link to get (active) option ??? also is it possible to have a switchable vco/non vco maybe with a toggle switch ???

[Carl-NC]

Connect R7 to Q3-G for active pull-down. Offhand, I don't see a straightforward way to switch between vco & non-vco. It may be possible but would likely require some circuit changes.

- Carl

[kt315]

dave, do with VCO only. do not addle a brain by those difficulties.

[daverave]

thanks Carl.

[daverave]

dave, do with VCO only. do not addle a brain by those difficulties.

Hi Kt315...i just thought be interesting to have a vco/non vco mode as on some of the commercial detectors....do you think vco is better than normal audio...i noticed that eric foster used vco in many of his designs...maybe more sensitive ????

[Qiaozhi]

Hi Kt315...i just thought be interesting to have a vco/non vco mode as on some of the commercial detectors....do you think vco is better than normal audio...i noticed that eric foster used vco in many of his designs...maybe more sensitive ????

I've tried both VCO and non-VCO on the Hammerhead, and the VCO is a little more sensitive. Also, the VCO option provides more target information. Instead of a solid beep-beep (it's either there, or it's not there) the VCO audio fluctuates differently for different targets.

[daverave]

I've tried both VCO and non-VCO on the Hammerhead, and the VCO is a little more sensitive. Also, the VCO option provides more target information. Instead of a solid beep-beep (it's either there, or it's not there) the VCO audio fluctuates differently for different targets.

Hi Qiaozhi....is it easier to id iron with a vco audio ????

[kt315]

Hi Kt315...i just thought be interesting to have a vco/non vco mode as on some of the commercial detectors....do you think vco is better than normal audio...i noticed that eric foster used vco in many of his designs...maybe more sensitive ????

eric is advanced man on it... if you want get 3000 p.p.s. it has be not good for direct sound modulation you hear. you have to take then a divider or vco. this is still one IC in circuit. eric puts vco (ne555) because it is more productive, classic and probed by him. there is not so special sensitive encrease but vco is more adaptive for hearing and maybe more informative.

[kt315]

Hi Qiaozhi....is it easier to id iron with a vco audio ????

there is not of such disc you see in VLF. it is PI... all metal... but if a signal is faint and brief it is a money, if loud and long it is a bottle cap. your ear is best id...

[daverave]

there is not of such disc you see in VLF. it is PI... all metal... but if a signal is faint and brief it is a money, if loud and long it is a bottle cap. your ear is best id...

thanks kt315...i will be experimenting soon with the hammerhead once ive made a coil of this cat6 cable....i do like vco as i have this on my tesoro lobo which is different to my other tesoro.

[kt315]

ok dave... I see you are already at seabeach! great!

I have gave you a link in russian, but it is not readable for you... there was told that cat6 has not something advantage. imho it is good only for big coil 60-80cm ie it is simple to gather.

[Qiaozhi]

Hi Qiaozhi....is it easier to id iron with a vco audio ????

You cannot ID iron with the Hammerhead, but (as KT315 said) different targets will produce different changes in tone. Coins will give a quick tone change, but bottle caps are smeared out. Target ID is not accurate using this method.

[daverave]

glad you like the photo kt315...that was taken in the summer and i found a 22ct 16 gram gold ring with an emerald....i sold it to a shop and regret that now cause the shop are selling it for about 5 times the price that they paid me...wish i had kept it as my best ring that ive found....i know you cannot id iron with a pulse detector but just wondered if the vco gives a different change in tone compared to the non vco which gives double blip on iron depending on which angle you scan...i really hoped the cat6 cable would be an advantage compared to normal single strand copper wire...otherwise there is no point me using it as it makes the coil more heavy...but i will experiment and see what results i get from this cat6 wire.

[kt315]

yup the ring is nice find specially for first time and first trip. congrats

Dave, have you learnt one layer spiral coil by Gary Chemelek? did you visit his site with the description how he does it?

[daverave]

yup the ring is nice find specially for first time and first trip. congrats

Dave, have you learnt one layer spiral coil by Gary Chemelek? did you visit his site with the description how he does it?

Hi kt315....yes have seen spiral coil but not keen on that design...maybe if coil was etched on a pcb that would be better...but for now i will stick to normal coils...what you think about basket and star coils ????