Questions About Construction Of The Australian Mystery Crystal Set

Started by Dave.H March 9, 2008
I've been looking at a number of simple crystal radio designs, and
I've found the Australian mystery crystal set, and am interested in
building that, mainly because it's an Australian design, and I've
heard it it's a pretty good performer. I only have 2 questions- can I
substitute the detector for a 1N34? and what is  double silk covered
wire and do I really have use that?  What's wrong with regular coil
wire? I can only find 23 SWG, 25 SWG, and 33 SWG where I need 24 SWG,
30 SWG.

Thanks

Dave
On Mar 10, 11:03 am, "Dave.H"  wrote:
> I've been looking at a number of simple crystal radio designs, and > I've found the Australian mystery crystal set, and am interested in > building that, mainly because it's an Australian design, and I've > heard it it's a pretty good performer. I only have 2 questions- can I > substitute the detector for a 1N34? and what is double silk covered > wire and do I really have use that? What's wrong with regular coil > wire? I can only find 23 SWG, 25 SWG, and 33 SWG where I need 24 SWG, > 30 SWG. > > Thanks > > Dave
Forgot to give the schematic http://www.clarion.org.au/crystalset/mystery.html
Dave.H wrote:

> I've been looking at a number of simple crystal radio designs, and > I've found the Australian mystery crystal set, and am interested in > building that, mainly because it's an Australian design, and I've > heard it it's a pretty good performer. I only have 2 questions- can I > substitute the detector for a 1N34? and what is double silk covered > wire and do I really have use that? What's wrong with regular coil > wire? I can only find 23 SWG, 25 SWG, and 33 SWG where I need 24 SWG, > 30 SWG. > > Thanks > > Dave
http://www.rwonline.com/pages/s.0055/t.5708.html Read that, it's interesing., don't know if it'll help you how ever. I'm guessing that if you used enamel wire you would be fine for what you're doing. -- http://webpages.charter.net/jamie_5"

"Dave.H" wrote:

> what is double silk covered wire
It's wire insulated with silk.
> and do I really have use that?
Not unless you want it to be 'period authentic'. Graham
On Mar 10, 11:45 am, Eeyore 
wrote:
> "Dave.H" wrote: > > what is double silk covered wire > > It's wire insulated with silk. > > > and do I really have use that? > > Not unless you want it to be 'period authentic'. > > Graham
Not really, I'm building it on a metal chassis (coil mounted above, vertically) and don't really care about vintage looks. I can't seem to find wire of the right diameter, though, that's the only part I've yet to find.
On 3/9/08 5:03 PM, in article
bf96e056-ebfc-4488-b9d1-20dd29d380cf@h11g2000prf.googlegroups.com, "Dave.H"
 wrote:

> I've been looking at a number of simple crystal radio designs, and > I've found the Australian mystery crystal set, and am interested in > building that, mainly because it's an Australian design, and I've > heard it it's a pretty good performer. I only have 2 questions- can I > substitute the detector for a 1N34? and what is double silk covered > wire and do I really have use that? What's wrong with regular coil > wire? I can only find 23 SWG, 25 SWG, and 33 SWG where I need 24 SWG, > 30 SWG. > > Thanks > > Dave
That's a great looking radio. Use 23 or 25 or whatever is handy. The significant difference between cotton covered and enamel covered wires is that cotton spaces the wires a little farther apart than will the enamel, and it will take slightly more cotton covered wire to lay on the same number of turns as the enamel wire. Bottom line is, the two coils would have slightly difference inductive reactance. The turns count is probably a swag anyhow, and it's the reason most xtal sets using wound coils, put on lots of turns with taps so the range of tuning can be easily changed (hint, hint). I don't know what a really good replacement for the 1N34 would be. I'd look for a Hot Carrier diode if nobody comes up with a part number. From an occasionally defective memory, I think the 1N82 may be one.
"Donald Duck  Bowey"

>> I only have 2 questions- can I >> substitute the detector for a 1N34? > > > I don't know what a really good replacement for the 1N34 would be.
** Try reading the damn question - fuckwit. ....... Phil
On 3/9/08 6:04 PM, in article 63jfp9F256cl0U1@mid.individual.net, "Phil
Allison"  wrote:

> > "Donald Duck Bowey" > >>> I only have 2 questions- can I >>> substitute the detector for a 1N34? >> >> >> I don't know what a really good replacement for the 1N34 would be. > > > ** Try reading the damn question - fuckwit. >
Sorry grampa. I'll try to do better next time. If you keep using those naughty words I'm going to tell on you.
> > > ....... Phil > >
Dave.H wrote:
> I've been looking at a number of simple crystal radio designs, and > I've found the Australian mystery crystal set, and am interested in > building that, mainly because it's an Australian design, and I've > heard it it's a pretty good performer. I only have 2 questions- can I > substitute the detector for a 1N34? and what is double silk covered > wire and do I really have use that? What's wrong with regular coil > wire? I can only find 23 SWG, 25 SWG, and 33 SWG where I need 24 SWG, > 30 SWG. > > Thanks > > Dave
You can use regular coil wire of whatever size you can get that is close, and the 1N34 is fine as the detector. Ed

"Dave.H" wrote:

> can I substitute the detector for a 1N34?
You might do rather well with a zero bias schottky diode. Failing that, any germamium point-contact type (like the 1N34) would be a decent sub. Graham
On Mar 12, 12:48 am, Sjouke Burry 
wrote:
> Dave.H wrote: > > On Mar 10, 11:45 am, Eeyore > > wrote: > >> "Dave.H" wrote: > >>> what is double silk covered wire > >> It's wire insulated with silk. > > >>> and do I really have use that? > >> Not unless you want it to be 'period authentic'. > > >> Graham > > > Not really, I'm building it on a metal chassis (coil mounted above, > > vertically) and don't really care about vintage looks. I can't seem to > > find wire of the right diameter, though, that's the only part I've yet > > to find. > > A metal chassis can influence performance very much, > because metal in front of a coil acts as a shorted > winding. > I advise to test things without a chassis, on a non-metal > table surface, and when it performs as intended, > try it in your metal housing. > I would choose a wooden or plastic box however.
I've been thinking about that, and decided to go with my original intention; mount everything on a piece of pine board, '20's style.
On 3/11/08 3:51 PM, in article 47475$47d70c71$45013908$18402@KNOLOGY.NET,
"amdx"  wrote:

> > "Don Bowey" wrote in message > news:C3FBEB75.B1D97%dbowey@comcast.net... >> On 3/11/08 5:15 AM, in article 91512$47d674c2$18d6b40c$1163@KNOLOGY.NET, >> "amdx" wrote: >> >>> >>> "Dave.H" wrote in message >>> news:039c2b9f-720f-49b2-ac76-3aada2bf0309@i12g2000prf.googlegroups.com... >>>> On Mar 11, 6:05 am, "amdx" wrote: >>>> >>>> *and what's this stuff about a D cell on a crystal radio :-) >>>> >>>> I got the idea from one of Dave Schmarder's radios, #26 >>>> >>>> http://www.schmarder.com/radios/crystal/26.htm >>> >>> Hi Dave, >>> My point was, the purists would shudder at the thought of an external >>> power source on a crystal radio. Now if you extract the power from a >>> strong >>> local and use that to amplify a weak signal then your doing good work. >>> Mike >>> >>> >> >> The tube isn't being used as an amplifier, it's diode is used as a >> switchable option to a SS diode. The battery is for it's filament. > > Ok then, the purists would shudder at the thought of an external > power source on a crystal radio. Now if you extract the power from a strong > local and use that to bias your diode then your doing good work. > Gees Don, your acting like Phil but without the name calling :-) > Mike
Geez Mike, why didn't you take time to see what the OP was doing? If you wish to really be a purist you should insist one should use a coherer for the detector, or a chunk of galena and a cats-whisker. I think it's a bit cool to have two different detectors and be able to switch between them, like in the good old days.
"Dave.H"  writes:

>On Mar 10, 11:03 am, "Dave.H" wrote: >> I've been looking at a number of simple crystal radio designs, and >> I've found the Australian mystery crystal set, and am interested in >> building that, mainly because it's an Australian design, and I've >> heard it it's a pretty good performer. I only have 2 questions- can I >> substitute the detector for a 1N34? and what is double silk covered >> wire and do I really have use that? What's wrong with regular coil >> wire? I can only find 23 SWG, 25 SWG, and 33 SWG where I need 24 SWG, >> 30 SWG. >> >> Thanks >> >> Dave
>Forgot to give the schematic >http://www.clarion.org.au/crystalset/mystery.html
Substitutes will work fine. All the other stuff is to make it look like a "period piece." Go to a rock shop and get some galena for the detector if you want to go retro. Steve. -- Steven D. Swift, novatech@eskimo.com, http://www.novatech-instr.com NOVATECH INSTRUMENTS, INC. P.O. Box 55997 206.301.8986, fax 206.363.4367 Seattle, Washington 98155 USA
"Don Bowey"  wrote in message 
news:C3FBEB75.B1D97%dbowey@comcast.net...
> On 3/11/08 5:15 AM, in article 91512$47d674c2$18d6b40c$1163@KNOLOGY.NET, > "amdx" wrote: > >> >> "Dave.H" wrote in message >> news:039c2b9f-720f-49b2-ac76-3aada2bf0309@i12g2000prf.googlegroups.com... >>> On Mar 11, 6:05 am, "amdx" wrote: >>> >>> *and what's this stuff about a D cell on a crystal radio :-) >>> >>> I got the idea from one of Dave Schmarder's radios, #26 >>> >>> http://www.schmarder.com/radios/crystal/26.htm >> >> Hi Dave, >> My point was, the purists would shudder at the thought of an external >> power source on a crystal radio. Now if you extract the power from a >> strong >> local and use that to amplify a weak signal then your doing good work. >> Mike >> >> > > The tube isn't being used as an amplifier, it's diode is used as a > switchable option to a SS diode. The battery is for it's filament.
Ok then, the purists would shudder at the thought of an external power source on a crystal radio. Now if you extract the power from a strong local and use that to bias your diode then your doing good work. Gees Don, your acting like Phil but without the name calling :-) Mike
>
On 3/11/08 5:15 AM, in article 91512$47d674c2$18d6b40c$1163@KNOLOGY.NET,
"amdx"  wrote:

> > "Dave.H" wrote in message > news:039c2b9f-720f-49b2-ac76-3aada2bf0309@i12g2000prf.googlegroups.com... >> On Mar 11, 6:05 am, "amdx" wrote: >> >> *and what's this stuff about a D cell on a crystal radio :-) >> >> I got the idea from one of Dave Schmarder's radios, #26 >> >> http://www.schmarder.com/radios/crystal/26.htm > > Hi Dave, > My point was, the purists would shudder at the thought of an external > power source on a crystal radio. Now if you extract the power from a strong > local and use that to amplify a weak signal then your doing good work. > Mike > >
The tube isn't being used as an amplifier, it's diode is used as a switchable option to a SS diode. The battery is for it's filament.
Dave.H wrote:
> On Mar 10, 11:45 am, Eeyore > wrote: >> "Dave.H" wrote: >>> what is double silk covered wire >> It's wire insulated with silk. >> >>> and do I really have use that? >> Not unless you want it to be 'period authentic'. >> >> Graham > > Not really, I'm building it on a metal chassis (coil mounted above, > vertically) and don't really care about vintage looks. I can't seem to > find wire of the right diameter, though, that's the only part I've yet > to find.
A metal chassis can influence performance very much, because metal in front of a coil acts as a shorted winding. I advise to test things without a chassis, on a non-metal table surface, and when it performs as intended, try it in your metal housing. I would choose a wooden or plastic box however.
"Dave.H"  wrote in message 
news:039c2b9f-720f-49b2-ac76-3aada2bf0309@i12g2000prf.googlegroups.com...
> On Mar 11, 6:05 am, "amdx" wrote: > > *and what's this stuff about a D cell on a crystal radio :-) > > I got the idea from one of Dave Schmarder's radios, #26 > > http://www.schmarder.com/radios/crystal/26.htm
Hi Dave, My point was, the purists would shudder at the thought of an external power source on a crystal radio. Now if you extract the power from a strong local and use that to amplify a weak signal then your doing good work. Mike
On Mar 11, 6:05 am, "amdx"  wrote:

*and what's this stuff about a D cell on a crystal radio :-)

I got the idea from one of Dave Schmarder's radios, #26

http://www.schmarder.com/radios/crystal/26.htm
On Mar 10, 12:11=A0am, "Dave.H"  wrote:

> I'll go with the 1N34. =A0I'm also going to install a 1S5 tube as a > second detector, switchable between the two, with a 'D' cell powering > the filament.
Gack! How about using a transistor (base -emitter of PN3904 connect B to coil, E to phones), and a 1k resistor from the collector to battery (+)? Battery (-) to ground. Or go low-tech and use a two-potato battery. <http://www.ehow.com/how_18637_make-potato-clock.html>
"Dave.H"  wrote in message 
news:940ac3e1-5a04-4881-8d2f-9db8558f5c5d@d21g2000prf.googlegroups.com...
> On Mar 10, 5:53 pm, Eeyore > wrote: >> "Dave.H" wrote: >> > can I substitute the detector for a 1N34? >> >> You might do rather well with a zero bias schottky diode. >> >> Failing that, any germamium point-contact type (like the 1N34) would be a >> decent sub. >> >> Graham > > I'll go with the 1N34. I'm also going to install a 1S5 tube as a > second detector, switchable between the two, with a 'D' cell >powering the > filament.
Hi Dave, I almost feel bad giving you this URL, it is so full of useful information that it may be a while before you have time to get anything done. See section 1. Out of the 29 atricles, I think 5 or 6 are about how to improve the diode/detector operation. Oh, and see #19, Ben discusses the 1932 "Mystery Crystal Radio" http://www.bentongue.com/xtalset/xtalset.html Have fun, Mike *and what's this stuff about a D cell on a crystal radio :-)