Maplin 160W (225W) bipolar amplifier design

bluevanman63 · 19th February 2008, 05:16 PM

Does any one have a copy of the parts list for this design (as published in old copies of the maplin catalogue and used in their diy disco consule many years ago). I have a schematic and a number of broken modules. Any help welcomed

john_ellis · 20th February 2008, 10:35 PM

Hi bluevanman63

Think this was the one with two pairs 2N3055/MJ2955 in the output?

If so the one I'm thinking of had BFY50's and suchlike. BUt these were never 80V transistors, had to use Vcer spec. which seemed dubious.

You could probably use 2N3019 for all NPN's and 2N4033's as PNP's for input & driver in TO-39 cans or with a bit of persuasion BD139/BD140's for all small signal devices.

cheers
John

minton 56 · 29th February 2008, 07:43 PM

I have a copy (scanned) of the page from a 1992 catalogue, it includes the circuit diagram, parts list and set up details. Happy to send you a copy.

sakis · 29th February 2008, 08:33 PM

a copy also .....

always interested how amplifiers worked in the past .....

especially if they are made with simple parts like 2n3055....

thanks

latala · 1st March 2008, 12:27 PM

I also have some maplin modules and would appreciate a copy if possible
ypu can e-mail it to me if poss
regards Trev

Vivek · 2nd March 2008, 01:53 AM

Hi, I would like to have a copy of that too.

Thanks and regards,
Vivek.

sakis · 4th March 2008, 12:34 PM

any news about this circuit ????

thanks

DaveCl · 1st December 2008, 05:13 AM

At last, someone who has the same AMP. I build mine back in 1995 i have used it for my mobile disco since. it's been a fantastic Amp until now. The bias circuit has gone a bit off track and as the amp warm up the bias reduces and turns off the transistors. cut a long story short while in a hurrt trying to fix it pick up the speaker leads and pluged it in. Puzzled by the no output turned it up only to find out that i had connected both channles together and burnt out two resistors on the board. Do you have any info on the amp such as a schematic and parts list. This has been such a good amp i really want to get it fixed. PLease help

Mooly · 1st December 2008, 04:56 PM

I remember these

It was a very basic circuit, should be easy to draw from a populated PCB.

jacks76 · 15th December 2008, 02:26 PM

Why not post to the forum ?

19th February 2008, 05:16 PM	#1
bluevanman63 diyAudio Member Join Date: Feb 2008	Maplin 160W (225W) bipolar amplifier design Does any one have a copy of the parts list for this design (as published in old copies of the maplin catalogue and used in their diy disco consule many years ago). I have a schematic and a number of broken modules. Any help welcomed

29th February 2008, 07:43 PM	#3
minton 56 diyAudio Member Join Date: Feb 2008	Maplin 160W amplifier I have a copy (scanned) of the page from a 1992 catalogue, it includes the circuit diagram, parts list and set up details. Happy to send you a copy.

29th February 2008, 08:33 PM	#4
sakis diyAudio Member Join Date: Jan 2006 Location: nea makri athens greece	may i have a copy also ..... always interested how amplifiers worked in the past ..... especially if they are made with simple parts like 2n3055.... thanks __________________ SERVICE ΕΝΙΣΧΥΤΩΝ ΚΑΙ ΙΑΠΩΝΙΚΩΝ ΜΗΧΑΝΗΜΑΤΩΝ ΗΧΟΥ www.eastelectronics.gr

2nd March 2008, 01:53 AM	#6
Vivek diyAudio Member Join Date: Nov 2000 Location: Bangalore, India	Hi, I would like to have a copy of that too. Thanks and regards, Vivek. __________________ Thank God for DIY audio.

4th March 2008, 12:34 PM	#7
sakis diyAudio Member Join Date: Jan 2006 Location: nea makri athens greece	any news any news about this circuit ???? thanks __________________ SERVICE ΕΝΙΣΧΥΤΩΝ ΚΑΙ ΙΑΠΩΝΙΚΩΝ ΜΗΧΑΝΗΜΑΤΩΝ ΗΧΟΥ www.eastelectronics.gr


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

20th February 2008, 10:35 PM	#2
john_ellis diyAudio Member Join Date: Sep 2006	Hi bluevanman63 Think this was the one with two pairs 2N3055/MJ2955 in the output? If so the one I'm thinking of had BFY50's and suchlike. BUt these were never 80V transistors, had to use Vcer spec. which seemed dubious. You could probably use 2N3019 for all NPN's and 2N4033's as PNP's for input & driver in TO-39 cans or with a bit of persuasion BD139/BD140's for all small signal devices. cheers John

1st March 2008, 12:27 PM	#5
latala diyAudio Member Join Date: Feb 2006 Location: staffordshire	I also have some maplin modules and would appreciate a copy if possible ypu can e-mail it to me if poss regards Trev

1st December 2008, 05:13 AM	#8
DaveCl diyAudio Member Join Date: Nov 2008	Maplin 160W (225W) At last, someone who has the same AMP. I build mine back in 1995 i have used it for my mobile disco since. it's been a fantastic Amp until now. The bias circuit has gone a bit off track and as the amp warm up the bias reduces and turns off the transistors. cut a long story short while in a hurrt trying to fix it pick up the speaker leads and pluged it in. Puzzled by the no output turned it up only to find out that i had connected both channles together and burnt out two resistors on the board. Do you have any info on the amp such as a schematic and parts list. This has been such a good amp i really want to get it fixed. PLease help

1st December 2008, 04:56 PM	#9
Mooly diyAudio Moderator Join Date: Sep 2007	I remember these It was a very basic circuit, should be easy to draw from a populated PCB.

15th December 2008, 02:26 PM	#10
jacks76 diyAudio Member Join Date: Sep 2006	Why not post to the forum ?

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Another CSS WR/FR design -- The Bipolar Bipoles	planet10	Full Range	92	6th December 2012 12:29 AM
Maplin 100W mosfet amplifier - power supply problem	HBrunt	Solid State	8	21st October 2011 01:04 AM
Yet another boring Bipolar amp design!	ceharden	Solid State	61	3rd March 2009 04:22 PM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read