Ibanez STL replacement pot help

[mc_deli]

Basic newb stuff apologies - my 25(?) year old Ibanez Super Tube STL has a broken pot shaft - the plastic D-shaft has sheared off - and the pot knob is missing.

Knob image: http://www.effectsdatabase.com/model/ibanez/master/stl
The pot is a PCB mount marked 504H 100kb

Can you help me track down these parts (pot and knob) - my browsing of Maplins, Small Bear, Digispot etc. has come to nothing so far...?

Thanks

[armdnrdy]

Suggestion:

If you supplied an image of the pot that your searching for instead of a distant picture of the effect box you will receive a few more "hits" of where to locate it.

I don't have X-ray vision!

[mc_deli]

Sorry, I thought it might be a standard part... anyway I got the macro lens out just for you Andy!



The plastic part of the d-shaft on the level pot has sheared off, leaving the hoop of metal. At least, I presume the hoop there is original and wasn't added by the previous owner (and clumsy pedal juggler) in @1989.

Any ideas what part this "504H 100kB" pot might be?
And any source for these d-shaft Ibanez knobs?

Thanks again

[zombiwoof]

Here is an Ibanez 100k D-shaft pot for 5-series pedals, does yours look like this (long plastic D-shaft, snap-in pot)?.  Maybe it will work in your pedal:

http://www.ebay.com/itm/181067054209?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

Al

Oops, you posted the pic just as I was posting this, I see your pot is slightly different, but if the mounting holes line up and the post assembly is the same height, the one I posted may work.  Yours is a 100k Linear (B) pot.

[armdnrdy]

Here is an Ibanez 100k D-shaft pot for 5-series pedals, does yours look like this (long plastic D-shaft, snap-in pot)?.  Maybe it will work in your pedal:

http://www.ebay.com/itm/181067054209?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

Al

It looks like his pot is threaded which secures the board to the enclosure.

[mc_deli]

Here is an Ibanez 100k D-shaft pot for 5-series pedals, does yours look like this (long plastic D-shaft, snap-in pot)?.  Maybe it will work in your pedal:

http://www.ebay.com/itm/181067054209?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

Al

It looks like his pot is threaded which secures the board to the enclosure.

Yes, you are right. The STL pots, as in my pic, are threaded, and the plastic d shaft is about 9mm long - shorter than I think shown in the ebay link.

Any other ideas for the pot, and also ideas for knobs?

[zombiwoof]

Here is an Ibanez 100k D-shaft pot for 5-series pedals, does yours look like this (long plastic D-shaft, snap-in pot)?.  Maybe it will work in your pedal:

http://www.ebay.com/itm/181067054209?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

Al

It looks like his pot is threaded which secures the board to the enclosure.

Yes, I guess the snap-in pots won't work in that case.  Maybe check Small Bear and see if he has anything similar, if he doesn't try contacting Ibanez support, they may carry parts for older pedals.  The STL is from the short-lived Master Series that came between the 9 and 10 series Ibanez pedals (Master Series pedals all had three-letter designations).

Al

[armdnrdy]

mc_deli,

If you could take some measurements of the footprint of the pot, I'm sure we can find a replacement.

It looks in the image that the board mounted solder pins are located on the bottom. Correct?

Take a measurement of the center spacing from pin to pin.
Then a measurement of the distance from the center of the pins to the snap in pin located 3/4 of the way back.
Also the dimension of the height off of the circuit board.

Pot such as this come in varying dimensions. 

[mc_deli]

I will do that shortly. Thanks for the help.

[mc_deli]

OK some measurements (no calipers so approx)...

Pot is almost square 13mm
Threaded part of the pot is 9mm diameter, 7mm length
d-shaft is 9mm length, the flat part of the "d" (slightly off centre/not quite the diameter) is 5mm.

The level pot (pic above) is labelled "Level V4" on the PCB, with sticker "504H 100kB" on the pot side.
In terms of connections: above the sticker (orientated as in the pic above) are two prongs that are just feet. On the opposite side there are three prongs soldered into the PCB via extruded feet. There are two further prongs - one on each side - soldered into the PCB.

... to add.. I am pretty sure the metal loop where the d-shaft should be is just a bodge and not original;)
... to comment... this STL design has two circuit boards, I/O/DC soldered onto the top, smaller board, and a ribbon connecting the two boards. Everything works - a miracle after 15 plus years in a box, but pots are scratchy and long overdue a spray.

Thanks in advance for any more hints!

[armdnrdy]

Okay...see the image on the right? that is called the footprint. That is the PC board layout taken from the actual dimensions of the part...in this case the board mounted pot.

If you look at the image to the left (the pot) you will see how they correspond.

The three "prongs" that are soldered to the board,  we need the dimensions from center to center of those prongs.
Then...if you draw a straight line through the middle of the three prongs.....from that line to the other "prongs" in the back. If you could draw and post dimensions that would be helpful. Use the drawing of the pot that I posted and write in your pots dimensions.

[mc_deli]

Hi, if I understand correctly:



The 3 prongs are 3.5mm apart (centre to centre) - 7mm overall
At the side it is 10mm to the centre of the soldered connections either side and another 3mm to the (unsoldered) feet.

Again, thanks for your patience

[zombiwoof]

I had another thought, I would bet that all the Master Series pedals used the same type of pots, so if you could pick up any non-working Master Series pedal for cheap on Ebay, chances are that one of the pots will be the 100k linear pot you need, and you'd have the other parts from the pedal as spare parts for the future.  You can tell that series of pedals by the designation, they all as I recall are named by three letters (CSL, CPL, etc.).  Usually, when a pedal is not working, it is a cap or other component that is to blame (or just a bad connection somewhere), and not the pots.  As I recall, all the Master Series pedals had black cases, and looked similar to the 10 series pedals that followed, which had different colored boxes for each type of pedal.  Just another idea in case you strike out elsewhere.

Al

[armdnrdy]

Hi, if I understand correctly:



The 3 prongs are 3.5mm apart (centre to centre) - 7mm overall
At the side it is 10mm to the centre of the soldered connections either side and another 3mm to the (unsoldered) feet.

Again, thanks for your patience

Yes....That's it!
This gives me something to work with.
Now if I find a replacement for you......you know that you are going to have to teach me how to post an image that doesn't take up the whole screen! 

[smallbearelec]

This pot:

http://www.smallbearelec.com/servlet/Detail?no=1139

in 100K linear is probably what you need, but the shaft is full round. If you can confirm that the size is right, buy one. Clamp the shaft in a vise (or locking-grip plier), Put On Goggles, and slice off half the shaft with a cutoff wheel on a Dremel tool...D-shaft.

Regards
SD

[armdnrdy]

This pot:

http://www.smallbearelec.com/servlet/Detail?no=1139

in 100K linear is probably what you need, but the shaft is full round. If you can confirm that the size is right, buy one. Clamp the shaft in a vise (or locking-grip plier), Put On Goggles, and slice off half the shaft with a cutoff wheel on a Dremel tool...D-shaft.

Regards
SD

Nope!
Good try Steve!
Your Alpha has a 2mm pitch. I believe that the pot in question is a Bourns. It may be obsolete.

[mc_deli]

Thanks Small Bear, I had looked at those and they don't seem quite right.

I just found this ebay seller of TS parts - I am waiting to hear more details on this part:
http://www.ebay.com/itm/Ibanez-100k-Level-Pot-fits-all-5-Series-Pedals-TS5-Tube-Screamer-and-others-/181067054209?pt=Guitar_Accessories&hash=item2a286ffc81
..to be honest I think it also lacks the thread

[armdnrdy]

There is a TS5 pot on my desk as I write this.

Years ago, I rehoused a TS5 into a "proper" metal enclosure....so I have the original hardware and misc. parts deleted for "mods."

If the measurements of the pot that you listed are correct, this pot won't work.

This pot measures:

pins: center to center (called pitch) 2.5mm
overall measurement (center to center outside pins) 5mm
center of pins to "snap in" pin: 7mm
distance between snap in pins: 10mm
pot body: 9.54mm X 11.43mm
shaft length: (from top of body to end of shaft) 18mm

[mc_deli]

Thanks for the info. The "pitch" is 3.5mm so, as you say, this won't work.

I think the best long term solution is to rehouse the pedal, and replace all four pots, the DC socket, jack sockets and the footswitch - I am in no way a fan of the original enclosure and I intend to keep this pedal for another eternity.

I need to practice with some other (less vintage) PCB soldering and desoldering first before I have a go at that - whence I will no doubt be back here for advice and admonition!

Until then we might have to admit defeat in this search

[zombiwoof]

Thanks Small Bear, I had looked at those and they don't seem quite right.

I just found this ebay seller of TS parts - I am waiting to hear more details on this part:
http://www.ebay.com/itm/Ibanez-100k-Level-Pot-fits-all-5-Series-Pedals-TS5-Tube-Screamer-and-others-/181067054209?pt=Guitar_Accessories&hash=item2a286ffc81
..to be honest I think it also lacks the thread

That is the same pot and seller I linked to earlier in this thread, and we already decided it wouldn't work.

Al