1960's Hitachi KM1410 car radio, aux in? - UK Vintage Radio Repair and Restoration Discussion Forum

janihei · 28th Jul 2019, 11:48 pm

Hi, need some help to add an audio input to my vintage Hitachi mono radio. The radio has a DIN 5-pin 240deg aux connector for tape receiver/recorder. Does someone know the pinout diagram for the 5-pin DIN connector?

'LIVEWIRE?' · 29th Jul 2019, 8:56 am

They were usually wired to a standard convention in which Pin1 was the detector o/p from the radio, pin2 the audio i/p to the radio's amplifier, pin3 Audio earth, pin 4 +12v, pin 5 Battery -ve (the latter two assume a Negative earth radio & vehicle- they would be -12v and battery +ve if Positive earth. If Hitachi followed the Blaupunkt pattern a Blanking Plug in which pins 1 & 2 are bridged will be inserted in the socket. Removal of that plug mutes the radio. Insertion of a suitably wired DIN Plug allows a Cassette deck, CD or MP3 Player, etc. to play (only in mono of course) through the radio. There are detailed notes, including diagrams of the DIN plugs &sockets in the 'sticky' thread at the top of this section.

janihei · 29th Jul 2019, 9:49 pm

Thanks to livewire, Pins 1 and 2 are indeed originally bridged. Do i need to filter the audio signal somehow or is it straight connecction.

'LIVEWIRE?' · 30th Jul 2019, 8:23 am

It depnds what you intend to play through the Hitachi. If a stereo source (Cassette player, CD or MP3 player, etc.) then combining/matching resistors at least will be needed. As I mentioned in my earlier post, there is a 'sticky' section which goes into some detail on how to add 'aux-in' connections to car radios, which will give you some idea as to how to proceed.

roffe · 30th Jul 2019, 12:38 pm

In the diagram that I have found on the net,it looks like this:

'LIVEWIRE?' · 30th Jul 2019, 1:27 pm

Apart from that being a 5-pin 180 deg. DIN Socket, where other brands used a 5 or 6 pin 240 deg. socket, that is exactly how I expected it to be wired, so removing the link between pins 1 7 3 mutes the radio. Any external input would then be taken to pins 3,5, & 2, using a screened lead with the inner going to pin 3 and the screen to pin 2.

Mike. Watterson · 30th Jul 2019, 3:59 pm

A pair of 33 Ohm resistors from any earphone jack to pins 3 & 5 with jack outer to pin 2.

janihei · 30th Jul 2019, 8:30 pm

OK, adaptor is ready and works great. Made adapter box and used 3.5mm jack terminal with switch, 4.7kohm resistors in signal leads. Pin 1=radio on/off. Pin 2=audio signal. Pin 3=audio ground.

Thanks for all!!

28th Jul 2019, 11:48 pm	#1
janihei Retired Dormant Member Join Date: Jul 2019 Location: Rauma, Finland. Posts: 3	1960's Hitachi KM1410 car radio, aux in? Hi, need some help to add an audio input to my vintage Hitachi mono radio. The radio has a DIN 5-pin 240deg aux connector for tape receiver/recorder. Does someone know the pinout diagram for the 5-pin DIN connector?

29th Jul 2019, 8:56 am	#2
'LIVEWIRE?' Rest in Peace Join Date: Mar 2006 Location: N.W. Oxfordshire(Chipping Norton) Posts: 7,306	Re: 1960's Hitachi KM1410 car radio, aux in? They were usually wired to a standard convention in which Pin1 was the detector o/p from the radio, pin2 the audio i/p to the radio's amplifier, pin3 Audio earth, pin 4 +12v, pin 5 Battery -ve (the latter two assume a Negative earth radio & vehicle- they would be -12v and battery +ve if Positive earth. If Hitachi followed the Blaupunkt pattern a Blanking Plug in which pins 1 & 2 are bridged will be inserted in the socket. Removal of that plug mutes the radio. Insertion of a suitably wired DIN Plug allows a Cassette deck, CD or MP3 Player, etc. to play (only in mono of course) through the radio. There are detailed notes, including diagrams of the DIN plugs &sockets in the 'sticky' thread at the top of this section.

29th Jul 2019, 9:49 pm	#3
janihei Retired Dormant Member Join Date: Jul 2019 Location: Rauma, Finland. Posts: 3	Re: 1960's Hitachi KM1410 car radio, aux in? Thanks to livewire, Pins 1 and 2 are indeed originally bridged. Do i need to filter the audio signal somehow or is it straight connecction.

30th Jul 2019, 8:23 am	#4
'LIVEWIRE?' Rest in Peace Join Date: Mar 2006 Location: N.W. Oxfordshire(Chipping Norton) Posts: 7,306	Re: 1960's Hitachi KM1410 car radio, aux in? It depnds what you intend to play through the Hitachi. If a stereo source (Cassette player, CD or MP3 player, etc.) then combining/matching resistors at least will be needed. As I mentioned in my earlier post, there is a 'sticky' section which goes into some detail on how to add 'aux-in' connections to car radios, which will give you some idea as to how to proceed.

30th Jul 2019, 12:38 pm	#5
roffe Hexode Join Date: Nov 2003 Location: Linkoping, Sweden Posts: 493	Re: 1960's Hitachi KM1410 car radio, aux in? In the diagram that I have found on the net,it looks like this: Attached Thumbnails

30th Jul 2019, 1:27 pm	#6
'LIVEWIRE?' Rest in Peace Join Date: Mar 2006 Location: N.W. Oxfordshire(Chipping Norton) Posts: 7,306	Re: 1960's Hitachi KM1410 car radio, aux in? Apart from that being a 5-pin 180 deg. DIN Socket, where other brands used a 5 or 6 pin 240 deg. socket, that is exactly how I expected it to be wired, so removing the link between pins 1 7 3 mutes the radio. Any external input would then be taken to pins 3,5, & 2, using a screened lead with the inner going to pin 3 and the screen to pin 2.

30th Jul 2019, 3:59 pm	#7
Mike. Watterson Heptode Join Date: Dec 2014 Location: Limerick, Ireland. Posts: 901	Re: 1960's Hitachi KM1410 car radio, aux in? A pair of 33 Ohm resistors from any earphone jack to pins 3 & 5 with jack outer to pin 2.

30th Jul 2019, 8:30 pm	#8
janihei Retired Dormant Member Join Date: Jul 2019 Location: Rauma, Finland. Posts: 3	Re: 1960's Hitachi KM1410 car radio, aux in? OK, adaptor is ready and works great. Made adapter box and used 3.5mm jack terminal with switch, 4.7kohm resistors in signal leads. Pin 1=radio on/off. Pin 2=audio signal. Pin 3=audio ground. Thanks for all!!