Correct wiring fo 700 series Handset - UK Vintage Radio Repair and Restoration Discussion Forum

richwk1 · 1st Apr 2010, 8:30 pm

Hi everyone could somebody provide me with the correct wiring colors for 700 series handsets i have done many but recently have had a few in that are wired the complete opposite the the way i normally do it. Now i am wondering have i done them correctly in the past. I normally do the earpiece looking at it with the terminals at the bottom red to the left terminal and green to the right.
I do the microphone looking at it with the terminals at the top white to the left and blue to the right is this correct or doesn't it make a difference. Opinions as always much appreciated.
Rich

Station X · 1st Apr 2010, 9:02 pm

It does not matter which way you connect the wires. Red and green to receiver. White and blue to the transmitter/mic.

russell_w_b · 1st Apr 2010, 9:04 pm

Doesn't make a ha'porth of difference. Red / green to receiver (there should only be AC on it anyway); blue / white to mic. It's just a carbon-filled variable resistor after all, and the type 21 electret insert has a bridge rectifier across the input so polarity isn't important.

richwk1 · 1st Apr 2010, 9:13 pm

Guys as always thanks for info. Its pretty much what i thought but i do have a bad habit of second guessing myself. I very much appreciate everyone that takes the time to help and advise, you all make my hobby the enjoyable pass time it should be.

Best Regards Rich

1st Apr 2010, 8:30 pm	#1
richwk1 Retired Dormant Member Join Date: Aug 2009 Location: Birmingham, West Midlands, UK. Posts: 80	Correct wiring fo 700 series Handset Hi everyone could somebody provide me with the correct wiring colors for 700 series handsets i have done many but recently have had a few in that are wired the complete opposite the the way i normally do it. Now i am wondering have i done them correctly in the past. I normally do the earpiece looking at it with the terminals at the bottom red to the left terminal and green to the right. I do the microphone looking at it with the terminals at the top white to the left and blue to the right is this correct or doesn't it make a difference. Opinions as always much appreciated. Rich

1st Apr 2010, 9:02 pm	#2
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,288	Re: Correct wiring fo 700 series Handset It does not matter which way you connect the wires. Red and green to receiver. White and blue to the transmitter/mic. __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.

1st Apr 2010, 9:04 pm	#3
russell_w_b Dekatron Join Date: Jul 2007 Location: Penrith, Cumbria, UK. Posts: 3,687	Re: Correct wiring fo 700 series Handset Doesn't make a ha'porth of difference. Red / green to receiver (there should only be AC on it anyway); blue / white to mic. It's just a carbon-filled variable resistor after all, and the type 21 electret insert has a bridge rectifier across the input so polarity isn't important. __________________ Regds, Russell W. B. G4YLI.

1st Apr 2010, 9:13 pm	#4
richwk1 Retired Dormant Member Join Date: Aug 2009 Location: Birmingham, West Midlands, UK. Posts: 80	Re: Correct wiring fo 700 series Handset Guys as always thanks for info. Its pretty much what i thought but i do have a bad habit of second guessing myself. I very much appreciate everyone that takes the time to help and advise, you all make my hobby the enjoyable pass time it should be. Best Regards Rich