1910 radio, crystal set
 

I just got a 1910 pat. date radio coil, married w/ a 1915 heaphones, w/ a solid state diode for better performance. Volume is medium, even loud somewhat depending on skip at times where headphone can be placed away from ears and still be easily heard .. Good earth ground and antenna coupled near one of the sets wires I believe produce a regen. effect to make station louder. A six to ten ft. antenna wire is all that's needed. CAN anybody show pics or plans to make a 1910 galena crystal detector setup? What does the double detectors do like in early AK sets???

DOES anybody here have a pre1919 or 1918 set here? Info is hard to find. NICE forever set, nothing to fail.

Nice set. Very little info on these early sets, as most were homebrew. The headsets looks like Baldwins, which are the ideal crystal set headphones. Are they type C's? If so, I believe they continued to sell those headphones well into the early 20s.

:music:I don't know if this is what you are looking for or not. Thought I would post it anyway. I built one like this about 50 years ago!

If all else fails, Amazon has a few books such as this:

http://www.amazon.com/Radios-That-Wo...7513273&sr=8-1

I got the spiral bound copy years ago... but I think that it was only about 10-15 bucks then.

not affiliated,
jr

Are you sure of the patent date on that crystal set? Commercial radio broadcasting in the United States did not begin until 1920. Anyone who had one of these sets in 1910 almost certainly had nothing to listen to, unless one counts experimental and/or amateur stations.

You can buy mounted chunks of galena and the cat whisker detector stands that they go into here:

http://www.xtalman.com/detectors.html

If you want to make the whole thing yourself, there is a good starting point here:

http://www.instructables.com/id/Buil...sker-detector/

For grins, here are a few pix of my 1920s Steinite xtal receiver. The xtal mount is fairly clearly shown in pix 2.

The patent date, IMHO does not really date your coil, as it is valid for 17 years after issue date... coil could have been made in the 20s, or it could have been used in the era of "spark gap" code transmissions in the teens.

jr

There were plenty of kids and men who experimented with radio fifteen years and more before broadcasting became common in the twenties. They built receivers, strung antennas, learned code, listened for code stations, and built transmitters from spark coils. This was going on from the early 1900's. Here and there some developed ways to transmit voice and phonograph records, etc. Here are a couple of boys transmitting and receiving in 1904. This website has many other interesting articles.

http://earlyradiohistory.us/1904ama.htm

I had a crystal set given to me, a homebrew with a 'Quaker Oats' coil (you can kinda read the label around the wire). I need to study it some more to learn just how to use it, there are a number of adjustments. With some fiddling I can pick up one station fairly clear (WBT-Charlotte, I think my antenna must be just right for them) but not a lot of volume.

Thanks for response one and all. What year is that article dangler, I've never seen a double slider coil?
This is basically the same as a loose coupler coil, just w/o the loose part. I believe this to be an early coil, is larger than most coils and lacks bakelite anywhere in construction. I have not seen any coil similair to this.

I believe this to be used when radio was experimental and or for wireless gap too.
The loose coupler coils go for a lot of money and accomplish same thing, most don't have any patent dates, teens mostly.
Yes, those are type C headphones, They ARE awesome!


Can anyone tell me what the benefit of a double galena detector like AK's does?

Does anyone have 1910 to 1915 galena construction details to give my set a period correct detector?

Thanks for early web info, info is sparse and scattered.

IS there any clubs that Have this type of stuff? I've had complicated inventions from last century, primitive items are zero maintainance.

I recently got interested in these, to have an early tube radio, you want early tubes. Those tubes are only getting more expensive. Just too involved for my interests.

Not to throw us too far off topic, but I highly recommend this article on a 1912 wireless set found almost totally intact at a garage sale! M.H. Dodd's station is important in that the equipment gives you a wonderful idea of what people who were into wireless were doing at the time; from the silver dimes soldered onto the key contacts, to reading all the pubs Gernsback was putting out:

http://www.radioblvd.com/DoddStation.html

Have you looked around on this board?

http://theradioboard.com/rb/viewforum.php?f=2

jr

A modern 1N34 or = diode will be as good or better (and a lot less trouble) than an early galena crystal where you scratch around with a catwhisker. Many different schemes were tried like double galena etc. but didn't prove to be any more sensitive than one good chunk of rock. However, a good piece of galena and a period-correct detector is fun to operate and is a trip back in time. Here are some pictures of various old and new galena/catwhisker setups:

http://www.google.com/search?tbm=isc...1489l1.11l12l0

And here are some raw parts for building your own detector stand:

http://www.google.com/search?tbm=isc...1489l1.11l12l0

You can buy the already mounted galenas as shown. I have also bought a hunk of galena about the size of a golf ball from a rock shop and it has a lot of hot spots on it and would yield enough to make dozens of detectors.

It's from 1923. The article came from a small booklet called "100 Radio Hookups" by Maurice L. Muhleman. It was published by The E.I. Company. I don't know if that was a forerunner of EICO or not. It pretty much covers everything from crystal sets to Regerative, Neutrodyne and Super Heterodyne radios using anywhere from one tube to six tubes.

There is one interesting diagram that uses a crystal detector and one tube for audio amplification. Probably an 01A.

If you,or anyone else,would like some of the diagrams,I would be more than happy to post them. There is a total of 48 pages. I also have another booklet titled "All American Radio-Hookups" by Rauland MFG. Co. It's also from 1923 and covers homebrew sets using only tubes. I'm sure some of you have heard of All American Mohawk. Same outfit. Hope this helps. Good luck. Dan

There was an interesting project in Popular Electronics (it might have been Electronics Illustrated) when hobby transistors first became available back in the late '50s. It was for a "free power" amplifying crystal set. It consisted of two receivers running off a single longwire antenna (though the 'crystals' used were 1N34 diodes). The first receiver used the carrier of a strong local station to provide rectified DC (a volt or so) to power a one-transistor amplifier. The second receiver could tune to any station and feed the audio to the transistor which amplified it, using nothing but the "free power" from the first station's carrier.

Re: "free power" crystal radio: people are still building these and some report feeding a speaker with such a set that can be heard a room away.

By golly you're right. And a bit of snooping reveals these interesting, related items..
http://www.ke3ij.com/nopower.htm
http://www.youtube.com/watch?v=gcui0K7JZXA

If you are near a very powerful station, say 10, 25 or 50kW (!), an arrangement like this could probably be heard at much greater distances. The transmitters for most Cleveland AM stations, for example, are located in a west-side suburb of the city, and if you are anywhere near them, an amplified crystal set tuned to any of them would probably be so loud as to be annoying, if not downright unbearable; an ordinary free-power set probably could drive a small loudspeaker to a decent listening volume.

The other problem with all crystal sets is poor to downright non-existent selectivity. If you are very near one or more high-power stations, your galena-crystal radio would have the heck of a time separating the signals; in fact, I think you would only hear a mishmash of noise, as your set received all the stations at once. I had a Remco crystal set when I was a kid. The radio worked well enough (using a 50-foot wire antenna in my back yard) to receive the local station in the next town west of me, and I'll never forget the time when, after that station signed off (it was an 0.5-kW daytime only station at that time, late 1960s-early seventies), I actually heard a faint signal from a top-40 rock station in the city of Cleveland, the transmitter being in a western suburb. The station itself was not that powerful, either, only running 5kW daytime and, IIRC, 1kW or less at night. I was living at the time in a Cleveland suburb some thirty miles from the transmitters of all the city's radio and TV stations, so I was surprised -- nay, astounded -- to hear that 5kW station on a crystal set, albeit faintly, like a gnat sighing through a window screen at 10 paces. The only thing I can figure is the propagation conditions that night must have been unusually good. Never heard any other Cleveland stations on that Remco free-power radio, though, and the radio itself is long gone. :no:


I hate to think how loud Cincinnati's WLW must have been on crystal sets when that station was running its 500-kW transmitter in the 1920s-'30s. A plain crystal set without an amplifier would have picked up the station with room-filling volume, and then some; one could probably use a speaker in place of headphones easily. However, I would hope that any crystal set driving a loudspeaker, with or without an amplifier, would have some sort of output limiter or even an actual control to allow the listener to reduce the volume if desired or if necessary -- especially if listening to a close-by 50-kW station.

The typical toy or oatmeal-box crystal set is very lossy which cuts both sensitivity and selectivity. The only power that an unamplified set has is the power coming in on the antenna, so for high performance, as much of that signal as possible has to be conserved. Many advanced crystal set constructors these days build sets with super low-loss tuning capacitors, air-core litz wire coils and special insulation techniques that are as sensitive as and separate stations as well as a superhet, as incredible as that may seem. Even the interchannel band flutter can be heard on some of these sets. If you search for "selective crystal set" or "crystal set contest," you'll find descriptions and pictures of such sets and see that many have logged up to hundreds of confirmed stations on their sets. Special techniques are used to keep losses low and to match sensitive headphones :music: to the high impedance of the set. These are unpowered sets and do not use amplification of any kind. In the case of a local flame thrower, a coil/cap wave trap can null it out.

thanks
 

Thanks for all replies, info is great, the most fun post I have done in a while.

Depending on skip and antenna used, headphone volume is medium to even loud at certain times. Those type C are awesome, just bought a second pair, going to sale other headphones, makes a big differance. I'm really sold on these type C phones.

Interesting link says 1n34a preferred crystal, I was using a silicon w/ good results. I saved a extra large old archaic 1948 sylvania 1n34 years ago, pulled from first tv I worked on, simply to save it since ITS very EARLY solid state diode. Volume is great now! set even works well no earth ground! Make's it perfect and portable to bring out to yard or anywhere to listen to. Will check additional info, Thanks.

There is a cross talk problem with two statios only part of the time. The slider can discriminate the primary station and cancel out the other, only happens part of time. Further improvements such as a tuning cap probaly will help with selectivity.

That video w/ Kent guy is amazing, his set is loud enough to drive a small speaker. Investing in time to tinker really makes a nicer set. Awsome homebrew. Everyone check out Ken't loose coupler. I would of kept it the same as first video since closely to vintage coupler, other video shows coupler wildly modified.

IF ANYONE BUILDS THEIR OWN LOOSE COUPLER, USE three slides, more selective w/ better results as video demonstrates.

Here's a better pic of set.

CAN someone please tell me the benefit of a Double galena Detector?????



:scratch2:

Experiments have been done since "ancient" times with multiple detectors. I believe in most cases little or no advantage was found when using more than one detector at a time in some rectifying circuit. On advanced sensitive sets, often several samples of detector are tried to find the "hottest" one. Some have used a switch to go between two diodes, to pick the more sensitive one. Then that one would be compared to another, and so on going through the stock of detector diodes.