Hello All,
I've been thinking about the Binson Echorec drum delay unit, which uses lots of stainless steel wire, wrapped around a wheel, then lathed down to a somewhat flat surface instead of tape. Here's an in-depth link to how the memory system works and a picture of the drum.
Binson Echorec Memory System, effectrode.com
I've been attempting to read about tape heads and how their form effects their use, but I'm having trouble understanding how to select them for certain applications. The Echorec heads are pretty much long gone, or show up rarely, so I'm searching for a possible replacement. Here are some techincal data and figures from the same effectrode website about the tape heads.
Tape Head Data, effectrode.com
So what I'm basically asking is, are these tape heads made specifically for a curved, stainless steel medium, or are these a somewhat more generic? I understand that they need to be oiled to not be run down from the drum, but would they be build tougher than tape heads because of this?
I'm not attemping to fix one, the general idea has just been on my mind and I've hit a road block at these tape heads.
Thanks for any info, I'm sure there are a few tape junkies on this forum! Cheers.
I've been thinking about the Binson Echorec drum delay unit, which uses lots of stainless steel wire, wrapped around a wheel, then lathed down to a somewhat flat surface instead of tape. Here's an in-depth link to how the memory system works and a picture of the drum.
Binson Echorec Memory System, effectrode.com
An externally hosted image should be here but it was not working when we last tested it.
I've been attempting to read about tape heads and how their form effects their use, but I'm having trouble understanding how to select them for certain applications. The Echorec heads are pretty much long gone, or show up rarely, so I'm searching for a possible replacement. Here are some techincal data and figures from the same effectrode website about the tape heads.
Tape Head Data, effectrode.com
So what I'm basically asking is, are these tape heads made specifically for a curved, stainless steel medium, or are these a somewhat more generic? I understand that they need to be oiled to not be run down from the drum, but would they be build tougher than tape heads because of this?
I'm not attemping to fix one, the general idea has just been on my mind and I've hit a road block at these tape heads.
Thanks for any info, I'm sure there are a few tape junkies on this forum! Cheers.
I suspect the heads are commercially available ones, filed down to clear the drum. A common tape head might have projections above and below the tape path, which would not matter to tape, but here, they would rub the drum. So if you look at some heads, keep that factor in mind. The photo looks like a full track head, rather than two or four track. I have not laid eyes on a full track head (by itself or in a deck) in decades. I think if we took a two track head and used half of it, it would work, but probably result in a weaker signal on the drum. Then again, I guess we could connect both sides in parallel.
But before going to far into DIY, I suggest you contact JRF and ask if they have any knowledge of these heads. They lap heads for the industry, so I expect they could grind any surface you wanted on an existing head. They are like THE head lapping people.
Head relapping
But before going to far into DIY, I suggest you contact JRF and ask if they have any knowledge of these heads. They lap heads for the industry, so I expect they could grind any surface you wanted on an existing head. They are like THE head lapping people.
Head relapping
Thanks for the tips.
I have seen mono cassette heads, might they be similar? I'm not sure if mono = full track. Nothing in the large reel to reel type though. They do have small protrusions, but they would be easy enough to dremel away.
I'll check out JRF, thank you!
I have seen mono cassette heads, might they be similar? I'm not sure if mono = full track. Nothing in the large reel to reel type though. They do have small protrusions, but they would be easy enough to dremel away.
I'll check out JRF, thank you!
I would call them on the phone, myself, rather than emailing the web page.
A cassette head will only have a 1/8" head width, while a 1/4" head will have the whole 1/4". I have never seen a mono cassette head in the sense of full track. For a mono cassette deck, are they not just tracks 1/3 or 2/4 just wired together? I don't remember, were early cassettes half track?
I recently sold off my Echoplex head stock. Seems to me those are full track heads, aren't they? An Echoplex playback head might be rare, but I think someone makes replacements. One of those might be reworked. MAybe they are half track mono, come to think of it.
No reason a cassette one couldn't work, but we are going to have half the footprint, so signal might be weaker.
We used to have those portable reel tape players in schools - the Webcor and similar. They were mono, but pretty sure it was half track, because the tapes had two sides to record. But if there are any old dead tape recorders around like that, you might steal a head from them.
regardless of my concerns with cassette heads, they are cheap, if not free, and no reason you should not experiment with them.
A cassette head will only have a 1/8" head width, while a 1/4" head will have the whole 1/4". I have never seen a mono cassette head in the sense of full track. For a mono cassette deck, are they not just tracks 1/3 or 2/4 just wired together? I don't remember, were early cassettes half track?
I recently sold off my Echoplex head stock. Seems to me those are full track heads, aren't they? An Echoplex playback head might be rare, but I think someone makes replacements. One of those might be reworked. MAybe they are half track mono, come to think of it.
No reason a cassette one couldn't work, but we are going to have half the footprint, so signal might be weaker.
We used to have those portable reel tape players in schools - the Webcor and similar. They were mono, but pretty sure it was half track, because the tapes had two sides to record. But if there are any old dead tape recorders around like that, you might steal a head from them.
regardless of my concerns with cassette heads, they are cheap, if not free, and no reason you should not experiment with them.
Ah man, I have to pick up the phone to talk to another human being? What is this, 2005? 😀
I'll give them a phone call.
I see an erase head from an echoplex with an asking price of $80! I thought the echoplex had a conjoined erase and playback, but I'll do some more looking.
Good info on the tape head widths. I found this mono tape head that seems to have a 1/8" opening that seems pretty square. Compared to the drawings on effectrode site, they seem to be taller, but not nearly as wide.
Your comments on signal strength, so I'd have to increase the signal going on to the recording medium. That might not be a bad thing - would that not increase the signal to noise ratio?
Can the wire wrapped drum be taller than the opening in the record head? Might make it harder to align, but are the tape tracks the same width of the tape head opening just because, or is that important?
I'll give them a phone call.
I see an erase head from an echoplex with an asking price of $80! I thought the echoplex had a conjoined erase and playback, but I'll do some more looking.
Good info on the tape head widths. I found this mono tape head that seems to have a 1/8" opening that seems pretty square. Compared to the drawings on effectrode site, they seem to be taller, but not nearly as wide.
Your comments on signal strength, so I'd have to increase the signal going on to the recording medium. That might not be a bad thing - would that not increase the signal to noise ratio?
Can the wire wrapped drum be taller than the opening in the record head? Might make it harder to align, but are the tape tracks the same width of the tape head opening just because, or is that important?
I do not KNOW those things, it is only thinking out loud that the smaller footprint makes for weaker signal laydown. it might just be the signal is noisier or something. recording hotter MIGHT improve things, but remember, the point of going hotter was to compensate for having only half the footprint to start with. You also can't jack it up forever, you can saturate things or overdrive the amp.
Echoplex had three heads. One was the R/P head, with erase too. The other was a straight playback head. And an erase head. yes $80 is about where they are selling. The ones I sold were NOS original Nortonics, and I was asking $150 for an R/P and a Playback, and that was a discount at that.
Google "magnetic tape head" and look through the images section. Many good drawings representing the innards of a head. The metal head is basically a shielded housing. The square dark hole in the face is the actual head works exposed. the dimension of that hole is not what is important. In your photo the vertical is crosswise to the tape. The little metal square within the dark one is the face of the pole pieces. You might see it under magnification, but in the center of that small center thing is a vertical slit - "the gap". That is what is important. Tape length is horizontal, and some like your photo extend only a short way along the tape, while other heads show metal there extending along the tape a ways. But the gap is what matters. It is only in the gap that the head manipulates the oxides on the tape.
As to what is laid down on the tape or drum, look at the little square in the dark hole. Now imagine it is a marker pen tip. It will lay down a stripe of signal on the drum, and only where it touches. the drum could be a millimeter wider or a foot wider, but only that part of the drum that little square crosses gets recorded. As long as the drum stays in the same plane, and the head does not bob up and down perpendicular to that, it will be aligned. When two heads are involved, the one that lays it down on the drum and the one picking it up, need to both be covering the same stripe. The tape or drum do not have tracks on them physically. the tracks on them are nothing more than the stripes of information laid on them by the heads.
Echoplex had three heads. One was the R/P head, with erase too. The other was a straight playback head. And an erase head. yes $80 is about where they are selling. The ones I sold were NOS original Nortonics, and I was asking $150 for an R/P and a Playback, and that was a discount at that.
Google "magnetic tape head" and look through the images section. Many good drawings representing the innards of a head. The metal head is basically a shielded housing. The square dark hole in the face is the actual head works exposed. the dimension of that hole is not what is important. In your photo the vertical is crosswise to the tape. The little metal square within the dark one is the face of the pole pieces. You might see it under magnification, but in the center of that small center thing is a vertical slit - "the gap". That is what is important. Tape length is horizontal, and some like your photo extend only a short way along the tape, while other heads show metal there extending along the tape a ways. But the gap is what matters. It is only in the gap that the head manipulates the oxides on the tape.
As to what is laid down on the tape or drum, look at the little square in the dark hole. Now imagine it is a marker pen tip. It will lay down a stripe of signal on the drum, and only where it touches. the drum could be a millimeter wider or a foot wider, but only that part of the drum that little square crosses gets recorded. As long as the drum stays in the same plane, and the head does not bob up and down perpendicular to that, it will be aligned. When two heads are involved, the one that lays it down on the drum and the one picking it up, need to both be covering the same stripe. The tape or drum do not have tracks on them physically. the tracks on them are nothing more than the stripes of information laid on them by the heads.
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