SEP1984 thunder jet ...

gittarasaurus wrote:you are gonna need some of these...

... the knobs were the reason that i couldn't do this re-build as original.  i nearly did a deal with the person that was going to sell me the UBC humbuckers to secure a pair of original knobs but he wanted £90 for them plus a pair of MMK-45s, one of which had a coil out.  at that sort of money, as i pointed out to him, i might as well put it towards a complete guitar.  also, he wanted to do the deal ex-eBay, and that was the point at which it fell through.

so, i've ordered a pair of these ...

https://www.ebay.co.uk/itm/25mm-black-grub-screw-amplifier-control-knob-multiple-solid-aluminium-ali-heavy/332450870488?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

... they're roughly the same size as the originals.  when they actually turn up, i'll know if they look alright.  at the moment i'm thinking that they might look a bit clumpy.

monkey wrote:

Westbone wrote:Wow! that should make it louder...

... it might if i put a push/pull on the tone control to switch the humbuckers between parallel and serial wiring, however, i haven't quite got my head around that yet. the three way switch would need changing and the humbucker ground connections get a bit complicated in serial with that kind of pickup selection. it'd be easier to use a rotary selector, though perhaps a bit odd looking.

... i think that i need to add some clarification here.  the coils on each humbucker are wired in series.  centre taping them will halve their output.  the 4 volume pots are just a simple way to adjust the contribution of each coil to the output.  the only real advantage of wiring the bridge and neck humbuckers in series is to maintain the level of output whilst both are centre tapped.  having the humbucker coils in series and the humbuckers themselves in series would double the output, however, there would be no point.  the existing parallel humbucker wiring already over-drives my mini-amp considerably - i have to back-off the volume a lot to get a really clean signal.  i've also got 10 gauge strings on the LTD EC-50, which means i can really twang them!

Pffft... 10 gauge strings are for softies!!   

You realise that you can, in fact, get those speed knobs in both notched and plain off eBay for pennies, yes??

Interesting pickup arrangement!

corsair wrote:You realise that you can, in fact, get those speed knobs in both notched and plain off eBay for pennies, yes??

... alas, i don't like them.  or, shall i say, not for this particular guitar.

but they go to 11!

gittarasaurus wrote:but they go to 11!

... i had noticed that.  i'm resisting the temptation of asking why.

monkey wrote:

Westbone wrote:Wow! that should make it louder...

... it might if i put a push/pull on the tone control to switch the humbuckers between parallel and serial wiring, however, i haven't quite got my head around that yet. the three way switch would need changing and the humbucker ground connections get a bit complicated in serial with that kind of pickup selection. it'd be easier to use a rotary selector, though perhaps a bit odd looking.

... i've sussed this out now.  the solution is to use the push/pull (DPDT) to select between serial and parallel, as i said, but instead of using the three way switch to select between signals, using it in ON-OFF-ON configuration (instead of ON-ON-ON) to short out the unwanted humbucker (so selecting just the neck humbucker really shorts out the bridge humbucker and vice versa, and selecting both humbuckers shorts out neither).

Well that sorts that out.... ...what about a blend pot?

Westbone wrote:Well that sorts that out.... ...what about a blend pot?

... i actually spent a lot of time thinking about using a blend pot per humbucker for the individual coils, and i kept wanting to use another blend pot to combine the humbuckers themselves. now, it helps to understand that the LTD EC-50 has a volume control per humbucker and a single tone control. because of the layout of these, it's not really ideal to add just 1 additional pot, as they'd spacially group 1:2:1. so, i decided that i'd add 2 additional pots, giving a spacial grouping of 2:2:1. so, that's bridge volume:neck volume:tone. to add the third blend pot, i'd have to loose the tone control. now, i always wang the tone control hard to the treble end, so perhaps i wouldn't have missed it. but the thing that i realised when i came up with the 4 volume pots solution is that it actually allows me more flexibility. the blend pots would allow me to pan between humbucker coil pairs and humbuckers. the 4 volume controls allow me to mix in any proportion of any coil. also, something i didn't mention, to keep things simple, is that each of the volume pots will be a push/pull (you can't do this with blend pots, as they're two pots stacked together), allowing me to select between serial, parallel, coil-1 and coil-2 on each of the humbuckers, as well as setting the level for each coil independent of the others. this is slightly double-bagging things but i want the flexibility to do virtually anything with this setup.

How about a PEQ pot...

monkey wrote:

gittarasaurus wrote:but they go to 11!

... i had noticed that.  i'm resisting the temptation of asking why.

... the most likely reason for this is simply to avoid copyright infringement.  if they'd been smarter, they'd have chosen a range of 0 to 8.  10 is an unnatural number base, due to having 8 fingers and 2 thumbs.

and, on this subject, would anyone like to enlighten me as to why there are 12 notes in an octave, not 16?  and what happened to B#/Cb and E#/Fb or, perhaps, why there is a G and G#/Ab?

Westbone wrote:How about a PEQ pot...

... in short, i didn't consider this.  having read this ...

https://westone.forumotion.com/t2554-peq-tone-controls

... i can honestly say that my sleep deprived brain is struggling a little to understand exactly what's going on here.  i'll give it some more thought, however, my initial impression is that it lacks symmetry ... and that always worries me!

monkey wrote:


and, on this subject, would anyone like to enlighten me as to why there are 12 notes in an octave, not 16?  and what happened to B#/Cb and E#/Fb or, perhaps, why there is a G and G#/Ab?

It's common sense when you think about it....

http://www.math.uwaterloo.ca/~mrubinst/tuning/12.html
"
The idea behind twelve is to build up a collection of notes using just one ratio. The advantage to doing so is that it allows a uniformity that makes modulating between keys possible. Without a compromise most keys would be unusable as most of the basic intervals would not be captured in the different keys (see the table at the end of this essay).
Unfortunately, no one ratio will do the trick exactly. However, the ratio of 3/2 happens to work reasonably well using 12 steps. With 3/2 as the basis for the scale, none of the above ratios besides a unison, fifth, and major 2nd are captured exactly.
However the most important constraint- namely that we get a repeating pattern going up in octaves, is almost satisfied by this scheme. Namely, after 12 applications of the ratios 3/2, we come back very close to where we started from (always dropping down by an octave, i.e. dividing by 2, each time the ratio exceeds 2):"

monkey wrote:

Westbone wrote:How about a PEQ pot...

... in short, i didn't consider this.  having read this ...

https://westone.forumotion.com/t2554-peq-tone-controls

... i can honestly say that my sleep deprived brain is struggling a little to understand exactly what's going on here.  i'll give it some more thought, however, my initial impression is that it lacks symmetry ... and that always worries me!

... so, i've given this a bit more thought.  it's basically using the resistance between 1/2 and 4/5 as circuit breaks to transition between parallel (1/2 and 4/5 closed circuit) and serial (1/2 and 4/5 open circuit) and the resistance between 5/6 is tone control for serial only.  i'm still a little hazy as to exactly what's happening when 2 and 5 (the resistance wipers) are between far left and centre (ie: neither closed circuit nor open circuit).  nevertheless, this doesn't give me the flexibility of effectively mixing any proportion of any coil (or, i don't think it does).  however, i'll give it some more thought.


i woke up this morning to the realisation that my solution for switching between parallel and serial for the humbuckers themselves needed an extra level of complexity to allow bridge or neck to be selected in either mode.  the solution is too complex for mere words.  it can be done but it involves ganging a second pair of switches to the 3-way pickup selector, one pair for each mode.

this one goes to eleven...    (<- clik  )

This one goes to 5...only...

Ah, yer all a bunch o' knobs!

You only just noticed!

... and the control cover (he says, trying desperately to keep this on track a little)???

How you getting on with the Thunder Jet body?

Westbone wrote:How you getting on with the Thunder Jet body?

... very little progress. i read up on drop filling, so i understand that now. i really want to get it functional before i plough a lot of time and effort into making it more presentable. the stereo jack is proving problematic. i can't find a completely black one. i ordered this on eBay ...

https://m.ebay.co.uk/itm/T-213J-6-35MM-JACK-SOCKET-CHASSIS-STEREO-/132360700227?txnId=1415171944003

... it's chrome!

Yeah, you just looked at the picture....

Try these
https://www.ebay.co.uk/itm/STEREO-1-4-GUITAR-JACK-SOCKET-6-35mm-STEREO-GUITAR-JACK-SOCKET-CR-BK-GD/181047404034?var=480206502053&hash=item2a27442602:g:oisAAOSwKtVWwiOH

Westbone wrote:Yeah, you just looked at the picture....

Try these
https://www.ebay.co.uk/itm/STEREO-1-4-GUITAR-JACK-SOCKET-6-35mm-STEREO-GUITAR-JACK-SOCKET-CR-BK-GD/181047404034?var=480206502053&hash=item2a27442602:g:oisAAOSwKtVWwiOH

... i haven't found a single all black stereo jack socket of this type on eBay. the one i ordered really did look like it was. believe me, i've looked at them all. the only all black stereo ones are the barrel type, and they're too large in diameter and pretty marginal in length too. there are lots of all black mono jack sockets.

Your getting to anal about it.

Westbone wrote:Your getting to anal about it.

... i'm mildly autistic. that's all!!!

i'd modify a mono one. i might still do this. the problem there is the stereo ones are deeper where the connection plates sit, by virtue of there being 3, not 2. painting a stereo one black might be a good option, but what with?

the other option is to get a black and chrome 3-way switch to match the jack socket. as it happens, the knobs, that still haven't arrived, have small chrome (aluminium) position indicators on them. so, that might work quite well.

I pointed you in exactly the right direction for a stereo jack above.
The same as original but stereo.It does fit perfectly. The nut on the original is black and the washer. The internal(bit where you put the jack in) is silver metal.
That's how they are. If you want something else that's your endevour

Can't help you further.

Westbone wrote:I pointed you in exactly the right direction for a stereo jack above.
The same as original but stereo.It does fit perfectly. The nut on the original is black and the washer. The internal(bit where you put the jack in) is silver metal.
That's how they are. If you want something else that's your endevour

Can't help you further.

... don't get me wrong here, i'm not complaining.  i gave up on doing this as original over the knobs.  the key word here is 'consistency'.  given that the original had black pole pieces, i thought that an all black selector and jack would be most consistent.  i hadn't bargained on no such jack existing in stereo form for the active pickups that i eventually decided to include in this re-build.

well, even i'm now getting frustrated with my lack of progress.

so, i've bought a black and chrome stereo jack and matching 3-way pickup selector switch (it even has a hex nut).

now, last night i decided to get my head around how to install the tesla AH-3 active humbuckers, and almost immediately ran into a potentially serious issue.  these are potted in resin.  so, no getting at the wire terminations inside them.  and the bridge pickup cable outer insulation is completely split just were it's potted into the humbucker enclosure.  i'm not quite sure whether to leave this alone or try to fix it in some way.  certainly, leaving it as is doesn't seem very satisfactory, as the stress on the wires could cause them to fail.

also, the wiring diagram for the tesla AH-3 active humbuckers has raised a couple of questions in my mind ...

http://teslapickups.co.kr/bbs/board.php?bo_table=g04_01

... see 'ACTIVE HUMBUCKER' 2 Active Humbuckers, 1 Volume, 1 Tone, 3 Way.

firstly, it appears that there might be separate outputs for each coil, as the white and black wires are joined together?

secondly, there appears to be a choice of using 9 volt or 18 volt battery power?

-if you think your item is defective, i would recommend returning it for a replacement.

-the tesla single coil active pickups have the same white and black wires for output as the humbucker.

-9v or 18v? EMG pickups offer the same choice, from their website:

Headroom (+9 or +18 Volts):
Headroom is defined as the ability of the pickup to deliver a clean, undistorted
waveform. But...while current is being drained from the battery, the battery
voltage is decreasing, and so is the headroom.
EMG Pickups never put out more voltage than is being supplied. Using a 9 Volt
battery will limit the output signal of the pickup to slightly less than 9 Volts.
Older EMG Pickups may have a maximum output of 4.5 Volts, one half of the
supply. If you supply the pickups with 18 Volts the headroom will double,
creating even more headroom for the signal. Doubling the supply voltage to 18
Volts will increase the amount of current drain. You don’t get something for
nothing

gittarasaurus wrote:-if you think your item is defective, i would recommend returning it for a replacement.

-the tesla single coil active pickups have the same white and black wires for output as the humbucker.

-9v or 18v? EMG pickups offer the same choice, from their website:

Headroom (+9 or +18 Volts):
Headroom is defined as the ability of the pickup to deliver a clean, undistorted
waveform. But...while current is being drained from the battery, the battery
voltage is decreasing, and so is the headroom.
EMG Pickups never put out more voltage than is being supplied. Using a 9 Volt
battery will limit the output signal of the pickup to slightly less than 9 Volts.
Older EMG Pickups may have a maximum output of 4.5 Volts, one half of the
supply. If you supply the pickups with 18 Volts the headroom will double,
creating even more headroom for the signal. Doubling the supply voltage to 18
Volts will increase the amount of current drain. You don’t get something for
nothing

... so, i sort of understand the headroom, however, i think that the bit about the battery voltage decreasing is a little misleading.  when the battery is spent, on-load the voltage will collapse but before that it ought to be fairly constant.  nevertheless, even if this really is an issue, the control cavity seems to be big enough to take 4 PP3 batteries (2 pairs).

anyway, i've put the pots, switch and jack on the guitar.  i've also re-drilled the 2 holes that i filled for the rear neck humbucke surround mounting screws.  and I've even managed to order the humbucker screws that were out of stock.

i've been giving some thought to the wiring.  i'm tempted to ditch the tone pot and have 2 push/pull volume pots, assuming that the humbucker coil outputs really can be split (otherwise, having a pair of wires for a single output is completely redundant - which it might well be).

i'm waiting for parts at the moment, most notably the wiring harness.

i've robbed some knobs, pro-tem, off a strat that i've stripped down in order to re-finish the body.

i'll check the resistance between the black and white wires on the tesla AH-3 active humbuckers. if they're short circuit, i'll know that there aren't separate coil circuits. my guess is there won't be.

i'm going to use some polystyrene to pack out the control cavity for the batteries (all 4 of them). it'll be light, unlike anything else on this guitar, and easy to shape too.

the most obvious omission is still the control cover. i'll guess that i'll have to make one.

monkey wrote:
i'm going to use some polystyrene to pack out the control cavity for the batteries (all 4 of them)

Why oh why oh why!!!

No wonder your called monkey...

What amp do you use?

Westbone wrote:

monkey wrote:
i'm going to use some polystyrene to pack out the control cavity for the batteries (all 4 of them)

Why oh why oh why!!!

No wonder your called monkey...

What amp do you use?

... i'll assume that you mean the batteries, not the polystyrene - because i'm thinking of having independently powered neck and bridge pickups in 18 volt mode (just possibly, i can use the 3-way pickup selector to switch power to them). and because i can. this is me experimenting.

and, for what it's worth, i tend to use a neewar acoustic NW-GA-1 mini amp, though i also have a line 6 spider IV 30.

also, monkey is an abbreviation of shock_the_monkey, which i use on another forum and is a track by peter gabriel on the album PG3.

Well all the very best monkey, hope you don't fry 'em.

Westbone wrote:Well all the very best monkey, hope you don't fry 'em.

... that has crossed my mind. i don't think it'll happen, after all, the outputs are shorted together with the 3-way switch in the middle position. and what would happen if either the ground or supply went open circuit on one of the humbuckers? my guess is that they're protected against that possibility.

i checked the resistance between the black and white wires on the tesla AH-3 active humbuckers last night.


neck: 0.7 ohms.


bridge: 0.5 ohms.


meter short circuit: 0.3 ohms.


as suspected, no separate coil circuits. a bit of a pity but no big surprise, really.


i also super-glued the split in the bridge humbucker cable. i massaged the outer insulation down the wires to close the gap in the split beforehand. possibly, this will be adequate.

at long last the guitar (or, rather, amp) knobs are here. and they look good! the pot shafts need setting back a bit but that's relatively trivial.

so, john lennon was wrong - happiness is an attractive guitar knob (or two)!

as for the LTD EC-50, i was going to fit a neck plate cushion, however, a couple of well rusted screws are thwarting my attempts so far. i have them soaking in WD40 at the moment. also, the mod i intended doing on the humbucker wiring keeps morphing. i just can't make my mind up. i tried laying out the extra knobs that i wanted to fit and, i have to say that, without extending the control cavity they'd look rather cramped. so, i'm contemplating a couple of balance pots and a master volume pot, possibly as an interim solution.

the tesla AH-3 active humbuckers are in, albeit using chrome mounting screws, as the black ones aren't here yet. the repair i did on the bridge humbucker cable seems to be alright. fortunately, the cable feeds directly into the hole in the body through to the control cavity, so it's not subject to having to bend very much as it comes out of the humbucker enclosure. i can't say they add much, aesthetically - they're a little bland. but perhaps i'll get used to that.


and the PP3 rechargeable batteries came today, so i've positioned them in the control cavity around the jack socket - one pair on either edge of the control cavity. this has revealed that the pot solder tabs need rotating to be towards the 3-way switch, rather than towards each other.


there's so little wiring to actually do that i'm thinking that i may as well do it myself, rather than wait for the wiring harness that i bought.


the next thing to do, i think, is to cut the polystyrene for the control cavity to locate the batteries. i'll also use this to dress the wiring, if i can.

Ya know...this is all um, interesting, but some pictures would help a lot.

Barry wrote:Ya know...this is all um, interesting, but some pictures would help a lot.

... now, i'm guessing that i'd need somewhere to host the pictures? i used to use photobucket but they did away with their free hosting, and i've never gotten around to doing anything about that, because i don't generally need to post pictures on the other forums that i frequent. i actually only used photobucket for avatars.

so, i checked out photobucket.  they seem to want $399.99 per year to host my pictures.  my microsoft outlook account costs me £14.99 per year, and i didn't even have to pay for that (the ad-free version)!

with a little luck, here should be a couple of pictures of the knobs that i took yesterday ...





... i'll add more pictures later today, all being well.

You can host your pix for free using Srvimg.com which is affiliated with the host company of this forum
Read this post for info
or click on the Host an Image icon in the editor

Barry wrote:You can host your pix for free using Srvimg.com which is affiliated with the host company of this forum
Read this post for info
or click on the Host an Image icon in the editor

... i'm using postimage, which is also free and is, i gather, specifically aimed at pictures intended to be used on forums. i certainly didn't pay photobucket their extortionate $399.99 per year, even though, as they say, it's just over $1 per day!

here's a picture of the rather bland tesla AH-3 active humbuckers in situ ...



and here's a picture of the control cavity, with the batteries (all 4 of them) taped in place ...



... it's very obvious why the pot tabs need re-positioning.  also, i'll likely have to change the 3-way switch to a leaf-type, as the box-type has a common pole that can't be used to power separate circuits, assuming that i choose to switch the positive rather than the negative (ground).

i didn't achieve much last night. i just cut out a template for the control cover. my method for such things is to take a piece of paper, put it over the item that i want to replicate (in this case, the control cavity), run my finger over the edge to get an outline on the paper, use a small torch to highlight the crease so produced, sketch over it using a propelling pencil, stick the paper to a piece of card, and finally cut the template out using a scalpel. it's a little on the large side, possibly because of the paper stretching a little, however, i can just trim down the actually control cover to a nice neat fit when i cut it out. i'm toying with using metal sheet, rather than the usual plastic. there are some very obvious pros and cons. so, not necessarily an easy decision. the plastic would undoubtedly be much easier.

i'm also toying with making a tray, instead of using polystyrene, to locate the batteries. again, some obvious pros and cons. the polystyrene is by far the simpler solution. the tray, however, could potentially double as screening, depending on what i make it out of, as i'd make it as an insert to be secured by the pots, switch and jack.

again, not much achieved. all i've done is to re-position the pots. and that's going to have been somewhat pointless, as i've decided to fit push/pulls. bereft of centre tapings, i've decided to use them for switching tone (not that i'm likely to want to, however, they'll be there should i decide to change the pickups at any time).

the knobs, i've decided, are a very good match for this guitar. in many ways i think that they're better than the originals. certainly, i'd recommend them to anyone looking to find replacements.

the two frozen neck screws on the LTD EC-50 are still not budging. i'm thinking that i need something better than WD40 to loosen the rust.

the A25K push/pull pots are on order ... from spain. i couldn't find them on eBay in the UK.

and i've decided to make the control cover from 2.3mm 1 ply gloss black plastic. i can always replace it with stainless steel at a later date, if i feel so compelled.

i'm thinking of using roller saddles. possibly not necessary, however, i like the ones that i fitted to the LTD EC-50.

i've also ordered a pair of chrome 'T' type strap buttons, as i think that they might give the body a cleaner outline. this seems far preferable to moving the strap buttons to the back of the body.

the roller saddles are ordered. i'm chasing the 1 ply gloss black plastic. the only obvious omission is the tone capacitors. oh, and i'm still waiting for the control wiring and the battery connectors.


and the WD40 loosened the rust on the LTD EC-50 neck plate screws sufficiently for one of them to release. i'm still soaking the other. i don't want to rush this, as the screw heads are not in a good state and i could easily distort the slotting.

the capacitors are now ordered. i've undoubtedly over-engineered them. any old capacitors probably would've done. but i went with the orange drop type.

the rusted screw in the LTD EC-50 neck plate is hanging in there. even with the other 3 screws out and turning the neck plate as much as i can (which isn't far, because of the way the body is shaped at the neck joint) it still isn't budging. if this were a strat it'd be out now.