What is the current state of understanding for GB1 knobs?

I know we know the side knobs (one being a dark green ham radio dial, etc) but the front seems to be pretty opaque.

I tried searching the forums but everyone seems to discuss the GB2 dials/knobs and not GB1 (likely due to us only having good photos of redressed GB2 props).

So… can anyone illuminate what the originals were? Are they known? Do we know decent close modern versions or reproductions?

As far as I’m aware none of the side knobs on the trap are dark green, all of the dark ones are black.

Sadly we’ve never been able to identify the source of the original knobs beyond the skirted Raytheon, the gold resistor, and maybe the small round black knob on the side with the gold resistor on the GB1 Traps, and its silver replacement in GB2.

I believe the speculation is that the rectangular knobs on the front of the Trap are slider knobs, but the source is sadly unknown.

Actually the front knobs were Identified in a build thread on here.

Both front knobs are ALCO brand and the silver one comes with different variations,

1/8 and 1/4 shafts and with the top already black like what’s seen in the film.

The black knob with the silver ring, knurling was changed over the years but it’s still being made but sadly nobody is selling them.

The Slider knobs are from a old lighting panel for stage lighting that is still being made today but hard to come by.

The GB1 side knob (as you call it “the small round black knob on the side with the gold resistor on the GB1 Traps”) is a super dark green. It’s a from a Heathkit HW SB Series Ham Radio. Comes with a skirt, but remove that and you have the exact side knob. It’s hard to see the difference between the very dark green and black in most lighting (eBay photos always make it look SUPER green tho, go figure).

For GB1?? I know the GB2 ones were identified… can you link the build thread? I couldn’t find it in my searching on here (I did think it slightly strange I couldn’t find that info here, seems like we’ve have got close by now)

Here’s the thread ps://www.gbfans.com/forum/viewtopic.php?f=3&t=40032&start=120

As far as the side knob being Black or Green Kingpin is correct.

The heathkit knobs that are all on Ebay that are listed as “Small” are too big and very dark green, the correct ones are Black, much smaller, fit a D-shaft and don’t feature a set screw.

Given that the correct ones have no clear photographs or references (and none exist on current traps) that’s a rather… boldly assertive claim. The Heathkit ones I have match the Sedgwick scenes perfectly (perfect size, shape, etc). You can get a lot of different sizes of Heathkit knobs, there’s a rather large range of sizes. Now if they are not the right ones I’d love to know what is because afaik no-one has an alternative (and most ppl seem to use resin copies of the Heathkit ones painted black anyhow).

However, that aside, thanks so much for that link. No wonder I couldn’t find it, it being buried in the depths of a build thread…

For future searchers, here are the links:

KN500A 1/8" (GB1 silver front knob)

http://tedss.com/2051000117

KU4025B 1/8" (GB1 small round black front knob) - annoyingly often out of stock.

http://tedss.com/2051000154

MS91528-1T1B (Raytheon pointer knob)

http://tedss.com/2051000492

Skirt for Raytheon knob (search for (KNB) Z31)

http://www.surplussales.com/shafthardware/Knobs-10.html

The metal and round ones are not confirmed to be the actual knobs but they are basically as close as anyone has been able to find. The Raytheon knob comes in a lot of variants. This one has the white stripe (like most of the screen used traps seem to have had) and no skirt around the base.

The Square knobs seem unidentified (that build thread just uses resin models in the kit he used).

So it seems like, while the front knobs aren’t exactly identified, we’re close to good with 3/4 of them. Square still unknown/sourced as far as I can tell.

While I can’t speak for all knobs produced by Heathkit (or whoever supplied them to Heathkit), I did purchase a Heathkit device in the hope they were the right kind, and in person they came across as too big, potentially even twice the size as what appeared to be used on the Ghost Trap. They appeared to be identical in size to these purchased by Dan Skinner:

Which, when viewed with the source material, are far too big:

Oh wow, that one is HUGE. Mine is the size of the one you’re comparing it to. Unfortunately it’s not like they have obvious part numbers and places just sell them as small/medium/etc. I picked up a lot that was several difference sizes and I guess I got lucky…?

But yeah, dang, I see why you’d say that if that’s what you have as reference.

Would you be able to post a picture of the knob you acquired?

I am running into the same issue of knobs being too big. The “small” Heathikit knobs that are available in several places are about 0.94" diameter max at the widest part. The ideal part is definitely smaller, though 1/2 the size I think is too small.

I’ll dig my crap out of storage this weekend if I can & find it (still in the build phase for a trap)

These are the two knobs I picked up for my self .

https://www.ebay.com/itm/162009058755

https://www.ebay.com/itm/292440888950

Wish I could have got one of those.

I picked up the same one. It’s exactly the same size as the resin casted GB1 knob I bought from Nick-A-Tron before he went out of business. I looked all over the knob it’s self and there are not markers for make or size anywhere on it. There are only markers on the actual switch and that was a dead end as far as the knob is concerned.

image

It doesn’t fit the switch I already had installed in my trap, so I’ll have to replace it or mode the switch.

Been trying to find the side knob. Even though this one is describes as the correct one, wanted to make sure first. As the price is a little high.

https://www.ebay.com/itm/Ghostbusters-Ghost-Trap-Side-Knob/114133127898?

EDIT

Was sent a decent offer and I accepted it. So hope it’s right.

I think that’s the same guy that has a listing on etsy for the knob.

Knob came yesterday. Perfect match to the casted piece I am replacing.

I had trouble finding these at all let alone in quantity for my Spirit Trap Cosmetic upgrade kits, so just made my own drawings and had a batch custom made out of aluminum then powder coated black. Recessed the bottom to allow some space for a nut to hold the pot or switch in place. I am happy how they turned out, though I did not have a real part so may not be exactly correct.

http://www.ghostlab42.com/img/SpiritTrap/IMG_9513_crop.jpg

https://www.ghostlab42.com/img/SpiritTrap/IMG_9513_crop.jpg

image

So I bought a set of knobs off a seller on Etsy that says they are GB1 Front knobs.

The Side knob I already had bought off ebay and the Silver knob with the a black top I also already had, having about it off TDESS a few years back. The set I bought came with that same exact knob with a silver top, but the one in GB has a black top. As you can see on the reference pictures on the main page from he Sedgewick scenes. The other three knobs came from the seller.

The Resin knobs below the real knobs are ones I bought from Nick-A-Tron that are suppose to be casts of the GB1 knobs.

This knob is almost exactly the same as the resin copy I got from Nick. Like I said I already had this knob, but the one the seller sent is exactly this knob, but just with a silver top instead of black.

This knob probably has the most dramatic difference between the resin copy I have and the actual knob I recieved. But look at the reference images this knob does seem to be smaller then the silver one, where as the resin ones I have are practically the same size. So I think this is more then likely correct and this knob is closer to what they used then the resin cast was.

This the “Slider” knob. The ones I got where shorter and fatter then the resin copies I have. Looking at the screen grabs from the movie I think this taller and thinner ones that I have resin casts of are closer to what was used then what I have here.

Anyway let me know what you guys think.

Yeah, that’s the exact Heathkit knob I was talking about earlier. Exact same size as mine.