Bush DAC90. Line level input? - UK Vintage Radio Repair and Restoration Discussion Forum

Electricdreams · 25th Apr 2018, 4:17 pm

I have been asked if I can put a line in the Bush DAC90 radio, for connection to bluetooth or mp3 player.

Can this be done?

Ed_Dinning · 25th Apr 2018, 4:25 pm

I'm afraid not, it could be highly dangerous as the DAC90 (and A) are both AC/DC sets with live chassis.

Ed

ThePillenwerfer · 25th Apr 2018, 4:46 pm

I'm with Ed.

It would be possible to do it safely using some sort of isolating transformer but there would still be a problem of switching the receiving part off when the MP3 player or whatever is connected.

A simple pantry transmitter is a better bet.

Graham G3ZVT · 25th Apr 2018, 4:49 pm

Quote:

Originally Posted by Ed_Dinning

I'm afraid not, it could be highly dangerous as the DAC90 (and A) are both AC/DC sets with live chassis.

Ed

Yes, but if the Bluetooth device and was entirely contained within the set and took its power from inside, there is no issue.

A cunning designer could arrange the radio to mute when BT audio is present.

Electricdreams · 25th Apr 2018, 5:29 pm

Hang on, I've just remembered a modern MW transmitter been demonstrated at Golborne. Does anyone have anymore information on that?

Murphy Maniac · 25th Apr 2018, 5:43 pm

PM sent re transmitter.

Herald1360 · 26th Apr 2018, 9:55 am

This general topic has been extensively discussed many times. In a nutshell, there needs to be some type of mains voltage rated isolation between the set and the source for it to be done safely. This can take many forms, some less costly than others if a deep junkbox is not available.......

Wireless (Bluetooth or otherwise), optical, transformer, isolation amplifier or even run the set from an isolating transformer are some options.

PsychMan · 26th Apr 2018, 10:05 am

I've wondered about the Bluetooth idea with the DAC90/DAC90A. One issue being no "gram" function would mean finding a non existent silent place on the dial, or some kind of switching to switch between Bluetooth and radio, without disabling the radio altogether but then it starts to sound like a messier job.

Nickthedentist · 26th Apr 2018, 10:17 am

Some of the BT modules do have an inbuilt audio switching function.

A "pantry transmitter" would be the least invasive and safest way though.

PsychMan · 26th Apr 2018, 10:41 am

That's useful to know Nick, thanks.

Ed_Dinning · 26th Apr 2018, 8:29 pm

Hi Gents, my original reply was based on a simple "add-on system".

There are safe ways to do this if you have the skill and knowledge, such as have been outlined above, but I am erring on the side of safety if such mods were done by, or come into the hands of non technical persons.

Ed

25th Apr 2018, 4:17 pm	#1
Electricdreams Hexode Join Date: Mar 2008 Location: Manchester, UK. Posts: 478	Bush DAC90. Line level input? I have been asked if I can put a line in the Bush DAC90 radio, for connection to bluetooth or mp3 player. Can this be done? __________________ What have you bought now??

25th Apr 2018, 4:25 pm	#2
Ed_Dinning Dekatron Join Date: Jan 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 8,195	Re: Bush DAC90 I'm afraid not, it could be highly dangerous as the DAC90 (and A) are both AC/DC sets with live chassis. Ed

25th Apr 2018, 4:46 pm	#3
ThePillenwerfer Octode Join Date: Mar 2011 Location: Sheffield, South Yorkshire, UK. Posts: 1,453	Re: Bush DAC90 I'm with Ed. It would be possible to do it safely using some sort of isolating transformer but there would still be a problem of switching the receiving part off when the MP3 player or whatever is connected. A simple pantry transmitter is a better bet. __________________ "Experts are only good at one thing: explaining why something will not work!"

25th Apr 2018, 5:29 pm	#5
Electricdreams Hexode Join Date: Mar 2008 Location: Manchester, UK. Posts: 478	Re: Bush DAC90 Hang on, I've just remembered a modern MW transmitter been demonstrated at Golborne. Does anyone have anymore information on that? __________________ What have you bought now??

25th Apr 2018, 5:43 pm	#6
Murphy Maniac Hexode Join Date: Aug 2009 Location: Liverpool, Merseyside, UK. Posts: 254	Re: Bush DAC90 PM sent re transmitter. __________________ Geoff. (BVWS Member)

26th Apr 2018, 9:55 am	#7
Herald1360 Dekatron Join Date: Feb 2007 Location: Leominster, Herefordshire, UK. Posts: 16,536	Re: Bush DAC90 This general topic has been extensively discussed many times. In a nutshell, there needs to be some type of mains voltage rated isolation between the set and the source for it to be done safely. This can take many forms, some less costly than others if a deep junkbox is not available....... Wireless (Bluetooth or otherwise), optical, transformer, isolation amplifier or even run the set from an isolating transformer are some options. __________________ ....__________ ....\|____\|\|__\|__\_____ .=.\| _---\__\|__\|_---_\|. .........O..Chris....O

26th Apr 2018, 10:05 am	#8
PsychMan Octode Join Date: Jun 2013 Location: Fleet, Hampshire, UK Posts: 1,765	Re: Bush DAC90 I've wondered about the Bluetooth idea with the DAC90/DAC90A. One issue being no "gram" function would mean finding a non existent silent place on the dial, or some kind of switching to switch between Bluetooth and radio, without disabling the radio altogether but then it starts to sound like a messier job.

26th Apr 2018, 10:17 am	#9
Nickthedentist Dekatron Join Date: Jan 2005 Location: Oxford, UK. Posts: 17,865	Re: Bush DAC90. Line level input? Some of the BT modules do have an inbuilt audio switching function. A "pantry transmitter" would be the least invasive and safest way though.

26th Apr 2018, 10:41 am	#10
PsychMan Octode Join Date: Jun 2013 Location: Fleet, Hampshire, UK Posts: 1,765	Re: Bush DAC90. Line level input? That's useful to know Nick, thanks.

26th Apr 2018, 8:29 pm	#11
Ed_Dinning Dekatron Join Date: Jan 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 8,195	Re: Bush DAC90. Line level input? Hi Gents, my original reply was based on a simple "add-on system". There are safe ways to do this if you have the skill and knowledge, such as have been outlined above, but I am erring on the side of safety if such mods were done by, or come into the hands of non technical persons. Ed