Book "Fun with Radio" by Gilbert Davey. - Page 2 - UK Vintage Radio Repair and Restoration Discussion Forum

Alistair D · 19th Jul 2011, 11:11 pm

Quote:

Originally Posted by Steve_Bell

I have a copy of the 1st edition, 1957, which I think is the best edition. I could be persuaded to scan and post the pages here, if there was any interest. It could take me some time though, as it is 64 pages.

Steve.

I used to borrow this from my local library in the early 60s. I would like a copy too.

Al

Herald1360 · 19th Jul 2011, 11:36 pm

Quote:

Originally Posted by Mark GØOIW

! How many mH?

I would reckon something with an inductive impedance of around 5-10K at the frequency of interest would do. Tricky bit is getting the self resonant frequency well above the range of interest- hence the various "pie wound" and other assorted techniques used. Effectively a set of series connected none (well not much) coupled lower inductance coils on a common former. TBH for medium waves a 4K7 resistor works passably well.

Mark GØOIW · 20th Jul 2011, 10:17 am

OOOH! A scan of an original Fun With Radio! Yes, please! Originals seem to sell at very silly prices.

I fancy a go at building a one valve MW / LW set. I last built one circa 1972 from a Home Radio kit. I have a suitable coil, purchased recently for a not unreasonable price - I think it's an Osmor (not Repanco).

I mostly remember reading Davey's books from the children's library when I was about 11. I enjoyed them but didn't build much as they were mostly valve based circuits, i.e. chassis bashing and expensive batteries. I built the two transistor set that just about worked, and a 2 x OC71 amp built on chocolate-block connectors (from Fun With Electronics, perhaps?).

Rob - you were lucky to discover Davey as at least his circuits worked. When I was around your age, I was given Illustrated Teach Yourself Radio that could have put me off electronics for life: see my posting elsewhere about the radio that never worked and never could have worked!

neon indicator · 20th Jul 2011, 11:51 am

See https://www.vintage-radio.net/forum/...0&postcount=95
and https://www.vintage-radio.net/forum/...3&postcount=81 for interesting one valve radio.

I was looking at the loop aerial design on the Vidor "Lady Margaret" and did some sums. If you wind a MW coil (or square/rectangle loop about 12" x 16") with two wires side by side, then when they are in parallel the coil is as if it's one fatter wire. (MW). If you connect the two coils in series then you have about x4 the inductance and the loop aerial (or coil) will work for most of LW.

LW is about 153 to 279kHz and MW about 540KHz to 1600kHz, so in reality to use the same capacitor the inductance would need to be x10 bigger. (Square law).
However LW is only 1.8:1 tuning range and MW is nearly 3:1 tuning range, so you can add a parallel capacitance to reduce the frequency.

So if the coil is 0.6mH with windings in Parallel it will be 2.4mH with windings in series.
If the tuning capacitor is 15pF to 180pF (possible MW), then MW is 484KHz to 1678kHz and LW is 188kHz to 280kHz, if you add an extra 120pF across tuning cap in LW.

Steve_Bell · 20th Jul 2011, 6:52 pm

I'll get scanning then! It will probably be the weekend before I get the time though.

Steve.

Steve_Bell · 22nd Jul 2011, 8:33 pm

I have now scanned the book and created a PDF file, which is 18MBytes. It's too big to post on the forum, so if you want a copy, please send me a PM with your email address and I'll post it to you.

Steve.

Alan Stepney · 23rd Jul 2011, 8:30 am

Thanks for taking the trouble to scan it.

There are several sites where you can store large files for others to download, or send large files via them.
Might be easier than posting it.

neon indicator · 23rd Jul 2011, 9:29 am

18Mbyte is too big for many email systems.

gezza123 · 23rd Jul 2011, 12:42 pm

Hi, yes please and thanks Steve, you have a PM.

Gezza

Red to black · 23rd Jul 2011, 1:22 pm

Hi Steve,

You have a PM.

Cheers,
Baz

Steve_Bell · 26th Jul 2011, 9:32 pm

Here is a link to download. http://www.mediafire.com/?x322rk57szy0tz2

Note that this site carries adverts, pop-ups, etc. but the link to the file is prominent.

Red to black · 26th Jul 2011, 10:01 pm

Excellent!

Thanks Steve

Cheers,
Baz

neon indicator · 26th Jul 2011, 10:13 pm

Thanks

dim-bulb · 26th Jul 2011, 10:14 pm

I have downloaded the book. Thanks for taking the time to scan it and to make it available.

Bob

gezza123 · 26th Jul 2011, 10:44 pm

Many thanks steve.Gezza

Alistair D · 26th Jul 2011, 10:52 pm

Oh the memories. Thanks from me too.

Al

neon indicator · 26th Jul 2011, 11:09 pm

p16 (p12 of pdf) appears to be the same radio as the BBC leaflet 1957.

I've established that you can wind a SW, MW or LW coil on suitable size "fizzy drink" bottle for these kind of radio. Superior to loo roll centres or Oats canisters. Also you can use the insulated wire pulled out of cheap Cat5 cable or Cat3 phone cable. No need to buy expensive Litz or drums of enamel wire. LW coil with 100T feedback coil on top of main coil using 2l bottle here https://www.vintage-radio.net/forum/...&postcount=103 360T was too much. I think 250 to 300T is enough for 4" diameter LW.

IJK2008 · 27th Jul 2011, 12:22 pm

Steve

Many thanks for your work in providing this.

Ian

Heatercathodeshort · 27th Jul 2011, 4:44 pm

I pulled this edition off the tip around 20 years ago. It is somewhat worn but complete with a good cover. I never thought such a simple book would prove so popular.

jeeefmfr · 27th Jul 2011, 7:17 pm

Steve,
Please could you email me a copy of "Fun with Radio" as I cannot access the mediafire site from the library as it is blocked.

My email takes 25MB max.

Thanks, Finlay.

20th Jul 2011, 10:17 am	#23
Mark GØOIW Tetrode Join Date: Jul 2007 Location: Caversham, Berkshire, UK. Posts: 53	Re: Book "Fun with Radio" by Gilbert Davey. OOOH! A scan of an original Fun With Radio! Yes, please! Originals seem to sell at very silly prices. I fancy a go at building a one valve MW / LW set. I last built one circa 1972 from a Home Radio kit. I have a suitable coil, purchased recently for a not unreasonable price - I think it's an Osmor (not Repanco). I mostly remember reading Davey's books from the children's library when I was about 11. I enjoyed them but didn't build much as they were mostly valve based circuits, i.e. chassis bashing and expensive batteries. I built the two transistor set that just about worked, and a 2 x OC71 amp built on chocolate-block connectors (from Fun With Electronics, perhaps?). Rob - you were lucky to discover Davey as at least his circuits worked. When I was around your age, I was given Illustrated Teach Yourself Radio that could have put me off electronics for life: see my posting elsewhere about the radio that never worked and never could have worked!

20th Jul 2011, 11:51 am	#24
neon indicator Retired Dormant Member Join Date: Jun 2010 Location: Co. Limerick, Ireland. Posts: 1,183	Re: Book "Fun with Radio" by Gilbert Davey. See https://www.vintage-radio.net/forum/...0&postcount=95 and https://www.vintage-radio.net/forum/...3&postcount=81 for interesting one valve radio. I was looking at the loop aerial design on the Vidor "Lady Margaret" and did some sums. If you wind a MW coil (or square/rectangle loop about 12" x 16") with two wires side by side, then when they are in parallel the coil is as if it's one fatter wire. (MW). If you connect the two coils in series then you have about x4 the inductance and the loop aerial (or coil) will work for most of LW. LW is about 153 to 279kHz and MW about 540KHz to 1600kHz, so in reality to use the same capacitor the inductance would need to be x10 bigger. (Square law). However LW is only 1.8:1 tuning range and MW is nearly 3:1 tuning range, so you can add a parallel capacitance to reduce the frequency. So if the coil is 0.6mH with windings in Parallel it will be 2.4mH with windings in series. If the tuning capacitor is 15pF to 180pF (possible MW), then MW is 484KHz to 1678kHz and LW is 188kHz to 280kHz, if you add an extra 120pF across tuning cap in LW.

20th Jul 2011, 6:52 pm	#25
Steve_Bell Hexode Join Date: Sep 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 475	Re: Book "Fun with Radio" by Gilbert Davey. I'll get scanning then! It will probably be the weekend before I get the time though. Steve.

22nd Jul 2011, 8:33 pm	#26
Steve_Bell Hexode Join Date: Sep 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 475	Re: Book "Fun with Radio" by Gilbert Davey. I have now scanned the book and created a PDF file, which is 18MBytes. It's too big to post on the forum, so if you want a copy, please send me a PM with your email address and I'll post it to you. Steve.

23rd Jul 2011, 8:30 am	#27
Alan Stepney Rest in Peace Join Date: Feb 2008 Location: Dorset, UK. Posts: 947	Re: Book "Fun with Radio" by Gilbert Davey. Thanks for taking the trouble to scan it. There are several sites where you can store large files for others to download, or send large files via them. Might be easier than posting it.

23rd Jul 2011, 9:29 am	#28
neon indicator Retired Dormant Member Join Date: Jun 2010 Location: Co. Limerick, Ireland. Posts: 1,183	Re: Book "Fun with Radio" by Gilbert Davey. 18Mbyte is too big for many email systems.

23rd Jul 2011, 12:42 pm	#29
gezza123 Heptode Join Date: Mar 2010 Location: Eastham, Wirral, Merseyside, UK. Posts: 788	Re: Book "Fun with Radio" by Gilbert Davey. Hi, yes please and thanks Steve, you have a PM. Gezza

23rd Jul 2011, 1:22 pm	#30
Red to black Nonode Join Date: Mar 2010 Location: Sunderland, Tyne and Wear, UK. Posts: 2,476	Re: Book "Fun with Radio" by Gilbert Davey. Hi Steve, You have a PM. Cheers, Baz __________________ I don't suffer from Insanity. I enjoy every minute of it.

26th Jul 2011, 9:32 pm	#31
Steve_Bell Hexode Join Date: Sep 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 475	Re: Book "Fun with Radio" by Gilbert Davey. Here is a link to download. http://www.mediafire.com/?x322rk57szy0tz2 Note that this site carries adverts, pop-ups, etc. but the link to the file is prominent.

26th Jul 2011, 10:01 pm	#32
Red to black Nonode Join Date: Mar 2010 Location: Sunderland, Tyne and Wear, UK. Posts: 2,476	Re: Book "Fun with Radio" by Gilbert Davey. Excellent! Thanks Steve Cheers, Baz __________________ I don't suffer from Insanity. I enjoy every minute of it.

26th Jul 2011, 10:13 pm	#33
neon indicator Retired Dormant Member Join Date: Jun 2010 Location: Co. Limerick, Ireland. Posts: 1,183	Re: Book "Fun with Radio" by Gilbert Davey. Thanks

26th Jul 2011, 10:14 pm	#34
dim-bulb Retired Dormant Member Join Date: Feb 2010 Location: New Germany, Nova Scotia, Canada Posts: 28	Re: Book "Fun with Radio" by Gilbert Davey. I have downloaded the book. Thanks for taking the time to scan it and to make it available. Bob

26th Jul 2011, 10:44 pm	#35
gezza123 Heptode Join Date: Mar 2010 Location: Eastham, Wirral, Merseyside, UK. Posts: 788	Re: Book "Fun with Radio" by Gilbert Davey. Many thanks steve.Gezza

26th Jul 2011, 10:52 pm	#36
Alistair D Nonode Join Date: Jan 2010 Location: Edinburgh, UK. Posts: 2,008	Re: Book "Fun with Radio" by Gilbert Davey. Oh the memories. Thanks from me too. Al __________________ I won't tell you how I discovered that.

26th Jul 2011, 11:09 pm	#37
neon indicator Retired Dormant Member Join Date: Jun 2010 Location: Co. Limerick, Ireland. Posts: 1,183	Re: Book "Fun with Radio" by Gilbert Davey. p16 (p12 of pdf) appears to be the same radio as the BBC leaflet 1957. I've established that you can wind a SW, MW or LW coil on suitable size "fizzy drink" bottle for these kind of radio. Superior to loo roll centres or Oats canisters. Also you can use the insulated wire pulled out of cheap Cat5 cable or Cat3 phone cable. No need to buy expensive Litz or drums of enamel wire. LW coil with 100T feedback coil on top of main coil using 2l bottle here https://www.vintage-radio.net/forum/...&postcount=103 360T was too much. I think 250 to 300T is enough for 4" diameter LW.

27th Jul 2011, 12:22 pm	#38
IJK2008 Hexode Join Date: Feb 2008 Location: Glasgow, UK. Posts: 321	Re: Book "Fun with Radio" by Gilbert Davey. Steve Many thanks for your work in providing this. Ian

27th Jul 2011, 4:44 pm	#39
Heatercathodeshort Dekatron Join Date: Jun 2005 Location: Warnham, West Sussex. 10 miles south of DORKING. Posts: 9,147	Re: Book "Fun with Radio" by Gilbert Davey. I pulled this edition off the tip around 20 years ago. It is somewhat worn but complete with a good cover. I never thought such a simple book would prove so popular. Attached Thumbnails

27th Jul 2011, 7:17 pm	#40
jeeefmfr Retired Dormant Member Join Date: Jul 2011 Location: Fife Posts: 1	Re: Book "Fun with Radio" by Gilbert Davey. Steve, Please could you email me a copy of "Fun with Radio" as I cannot access the mediafire site from the library as it is blocked. My email takes 25MB max. Thanks, Finlay.