Crystal Radio driving a Speaker - UK Vintage Radio Repair and Restoration Discussion Forum

vu2nan-nandu · 8th Aug 2014, 7:19 pm

Here's the link.

http://nandustips.blogspot.in/2014/0...g-speaker.html

Regards,

Nandu.

Herald1360 · 8th Aug 2014, 11:36 pm

How long was the aerial? (Part 5?)

vu2nan-nandu · 9th Aug 2014, 5:20 am

How long was the aerial? (Part 5?)[/QUOTE]

Hi Herald 1360,

Part 5 is a 60' vertical random wire!

Yesterday readability was 'inches away' from a tiny speaker. Today it's 'a metre away' from a 8" Phillips 10W dual-cone speaker.

The blog post has been updated.

Many thanks.

Regards,

Nandu.

robjkmannering · 9th Aug 2014, 7:13 am

I suspect that the 10W speaker was well within the power rating!
Seriously, I am amazed that this works at all.

Rob

peter_scott · 9th Aug 2014, 8:11 am

I have a BTH crystal set and a BTH horn loudspeaker and in the past have been able to hear a local station (about 25 miles away) at the other side of a room (about 15 feet away). I was just using the outer of a TV down lead as my aerial.

Peter

terrybull · 9th Aug 2014, 8:48 am

I remember seeing a radio design years ago that used a crystal detector to produce a voltage which in turn powered a receiver that used SB transistors. You needed to be close to a powerful transmitter for it to work.

KeithsTV · 9th Aug 2014, 9:14 am

I remember listening to Radio 2 on LW on a crystal set using a telephone earpiece. Mind you I was standing next to the transmitter at the time during a visit to Droitwich.

Keith

vu2nan-nandu · 9th Aug 2014, 2:59 pm

Quote:

Originally Posted by peter_scott

I have a BTH crystal set and a BTH horn loudspeaker and in the past have been able to hear a local station (about 25 miles away) at the other side of a room (about 15 feet away)

Hi Peter,

Yes, nothing to beat a balanced armature earpiece feeding a horn.

Quote:

Originally Posted by terrybull

I remember seeing a radio design years ago that used a crystal detector to produce a voltage which in turn powered a receiver that used SB transistors. You needed to be close to a powerful transmitter for it to work.

Hi Terrybull,

That's 'free-power' too! It'll be worth trying.

Quote:

Originally Posted by KeithsTV

I remember listening to Radio 2 on LW on a crystal set using a telephone earpiece. Mind you I was standing next to the transmitter at the time during a visit to Droitwich

Hi Keith,

Mine sounds quite strong on a balanced armature earpiece.
The station is just 35km away!

Regards,

Nandu.

8th Aug 2014, 7:19 pm	#1
vu2nan-nandu Pentode Join Date: Jul 2014 Location: Bangalore, India Posts: 132	Crystal Radio driving a Speaker Here's the link. http://nandustips.blogspot.in/2014/0...g-speaker.html Regards, Nandu.

8th Aug 2014, 11:36 pm	#2
Herald1360 Dekatron Join Date: Feb 2007 Location: Leominster, Herefordshire, UK. Posts: 16,535	Re: Crystal Radio driving a Speaker How long was the aerial? (Part 5?) __________________ ....__________ ....\|____\|\|__\|__\_____ .=.\| _---\__\|__\|_---_\|. .........O..Chris....O

9th Aug 2014, 5:20 am	#3
vu2nan-nandu Pentode Join Date: Jul 2014 Location: Bangalore, India Posts: 132	Re: Crystal Radio driving a Speaker How long was the aerial? (Part 5?)[/QUOTE] Hi Herald 1360, Part 5 is a 60' vertical random wire! Yesterday readability was 'inches away' from a tiny speaker. Today it's 'a metre away' from a 8" Phillips 10W dual-cone speaker. The blog post has been updated. Many thanks. Regards, Nandu.

9th Aug 2014, 7:13 am	#4
robjkmannering Retired Dormant Member Join Date: May 2009 Location: Norwich, Norfolk, UK. Posts: 717	Re: Crystal Radio driving a Speaker I suspect that the 10W speaker was well within the power rating! Seriously, I am amazed that this works at all. Rob

9th Aug 2014, 8:11 am	#5
peter_scott Dekatron Join Date: May 2003 Location: Edinburgh, UK. Posts: 3,274	Re: Crystal Radio driving a Speaker I have a BTH crystal set and a BTH horn loudspeaker and in the past have been able to hear a local station (about 25 miles away) at the other side of a room (about 15 feet away). I was just using the outer of a TV down lead as my aerial. Peter __________________ http://www.nostalgiatech.co.uk https://www.youtube.com/c/PeterScott/videos

9th Aug 2014, 8:48 am	#6
terrybull Octode Join Date: Jan 2011 Location: Southwell, Nottinghamshire, UK. Posts: 1,780	Re: Crystal Radio driving a Speaker I remember seeing a radio design years ago that used a crystal detector to produce a voltage which in turn powered a receiver that used SB transistors. You needed to be close to a powerful transmitter for it to work.

9th Aug 2014, 9:14 am	#7
KeithsTV Nonode Join Date: Aug 2007 Location: South Bradford, West Yorkshire, UK. Posts: 2,573	Re: Crystal Radio driving a Speaker I remember listening to Radio 2 on LW on a crystal set using a telephone earpiece. Mind you I was standing next to the transmitter at the time during a visit to Droitwich. Keith