Marantz model 18

C

calman46

Journeyman
#1
Joined
May 9, 2012
Messages
153
Location
MA
#1
I'm looking into the possibilities of making a power transformer for my model 18 . I have the original E & l laminates . There are no AC voltages on 18 schematic but I'm told I can use the the ones on the model 19 . The primary on the 18 was two coils in parallel , I was going to use 1 . Its the secondary that raises issues ,as it is drawn all the taps share the same CT is that right? I may omit the HV winding for the scope (transformer's Achilles Heal ) there is an work around for adding another transformer (looking into it) . Do you think its feasible to make one ? I'll post the schematic shortly . Thanks
 

Attachments

Last edited:
WOPL Sniffer

WOPL Sniffer

Veteran and General Yakker
#3
Joined
Aug 10, 2015
Messages
11,230
Location
Minnie-Soda
Tagline
Screw it
#3
calman46 said:
I'm looking into the possibilities of making a power transformer for my model 18 . I have the original E & l laminates . There are no AC voltages on 18 schematic but I'm told I can use the the ones on the model 19 . The primary on the 18 was two coils in parallel , I was going to use 1 . Its the secondary that raises issues ,as it is drawn all the taps share the same CT is that right? I may omit the HV winding for the scope (transformer's Achilles Heal ) there is an work around for adding another transformer (looking into it) . Do you think its feasible to make one ? I'll post the schematic shortly . Thanks
Click to expand...
Go back to your post and click "Edit", then double click on your picture, there is a box you can check for Large picture. Were all old with bad eyes.
 
WOPL Sniffer

WOPL Sniffer

Veteran and General Yakker
#6
Joined
Aug 10, 2015
Messages
11,230
Location
Minnie-Soda
Tagline
Screw it
#6
calman46 said:
I'm looking into the possibilities of making a power transformer for my model 18 . I have the original E & l laminates . There are no AC voltages on 18 schematic but I'm told I can use the the ones on the model 19 . The primary on the 18 was two coils in parallel , I was going to use 1 . Its the secondary that raises issues ,as it is drawn all the taps share the same CT is that right? I may omit the HV winding for the scope (transformer's Achilles Heal ) there is an work around for adding another transformer (looking into it) . Do you think its feasible to make one ? I'll post the schematic shortly . Thanks
Click to expand...
Are you sure the numbers written in red are correct for your AC Voltages? I't doesn't look right to me.
 
WOPL Sniffer

WOPL Sniffer

Veteran and General Yakker
#7
Joined
Aug 10, 2015
Messages
11,230
Location
Minnie-Soda
Tagline
Screw it
#7
calman46 said:
I'm looking into the possibilities of making a power transformer for my model 18 . I have the original E & l laminates . There are no AC voltages on 18 schematic but I'm told I can use the the ones on the model 19 . The primary on the 18 was two coils in parallel , I was going to use 1 . Its the secondary that raises issues ,as it is drawn all the taps share the same CT is that right? I may omit the HV winding for the scope (transformer's Achilles Heal ) there is an work around for adding another transformer (looking into it) . Do you think its feasible to make one ? I'll post the schematic shortly . Thanks
Click to expand...
Are you sure the numbers written in red are correct for your AC Voltages? I't doesn't look right to me. One side of the Bridge Rectifier (red wire) says 25 while the other says 15..... Hmmmm according to the drawing of the transformer, those should be really close. And is that 360 VAC on the anode of that diode??? Which is connected to you 6.3 VAC??? Naw
 
WOPL Sniffer

WOPL Sniffer

Veteran and General Yakker
#9
Joined
Aug 10, 2015
Messages
11,230
Location
Minnie-Soda
Tagline
Screw it
#9
I do believe on your secondary, the same color wires should be pretty close to the same. The transformer looks to be balanced so if the reading you have written in red are what you have on your amp, you got BIG ISSUES.
 
C

calman46

Journeyman
#10
Joined
May 9, 2012
Messages
153
Location
MA
#10
The bridge has 25.5v on each side ,just the way I made the 2 . These AC voltages are from the Model 19 schematic . I'm told its the same transformer. I don't have a transformer in unit,I just have the iron from it. A so called rewinder told me he could wind me a new one (HV was out on mine) but after he ripped all apart he said he couldn't do it .
 
Last edited:
Gepetto

Gepetto

Administrator
Staff member
#11
Joined
May 15, 2011
Messages
13,553
Location
Sterling, MA
Tagline
Old 'Arn Enthusiast
#11
calman46 said:
The bridge has 25.5v on each side ,just the way I made the 2 . These AC voltages are from the Model 19 schematic . I'm told its the same transformer. I don't have a transformer in unit,I just have the iron from it. A so called rewinder told me he could wind me a new one (HV was out on mine) but after he ripped all apart he said he couldn't do it .
Click to expand...
Just about anyone of us could have done that :)
 
WOPL Sniffer

WOPL Sniffer

Veteran and General Yakker
#12
Joined
Aug 10, 2015
Messages
11,230
Location
Minnie-Soda
Tagline
Screw it
#12
calman46 said:
The bridge has 25.5v on each side ,just the way I made the 2 . These AC voltages are from the Model 19 schematic . I'm told its the same transformer. I don't have a transformer in unit,I just have the iron from it. A so called rewinder told me he could wind me a new one (HV was out on mine) but after he ripped all apart he said he couldn't do it .
Click to expand...
The leg with 360vac can't be right. Even a WOPL with 500 watts ain't that high
 
WOPL Sniffer

WOPL Sniffer

Veteran and General Yakker
#13
Joined
Aug 10, 2015
Messages
11,230
Location
Minnie-Soda
Tagline
Screw it
#13
That would be a tough job getting the secondary right. A lot of shit if you don't have all the winders notes available.
 
C

calman46

Journeyman
#15
Joined
May 9, 2012
Messages
153
Location
MA
#15
right the 360AC winding is for the scope . I want to make just the power transformer for the unit . There is work around for adding another transformer for the scope . What I don't understand is all the other windings share the same CT. Its drawn like one winding, how would you where to put the CT? So could you make 3 different windings each with a CT and then connect them all to G ? Or are the Blue and Green windings really center tapped . Finding a 18 with a working scope is rare ,most HV winding have burnt out I'm told.
 
laatsch55

laatsch55

Administrator,
Staff member
#16
Joined
Jan 14, 2011
Messages
74,244
Location
Gillette, Wyo.
Tagline
Halfbiass...Electron Herder and Backass Woof
#16
It's drawn like one winding because it is, the different voltages are where a tap is brought out. You'll notice two SEPERATE windings on the bottom of the drawing. The center tapped windings will be measured with one lead of your meter on the center tap (ground). That's why you see a blue on each side of the center tap, and green etc...
 
orange

orange

Veteran and General Yakker
#17
Joined
Jul 6, 2010
Messages
17,704
Tagline
Broken beyond repair but highly affable
#17
Gepetto said:
Just about anyone of us could have done that :)
Click to expand...
And I could have lost it long enough for you to find and buy the actual part.

No thanks needed, it's a natural talent. :iconbiggrin:
 
oldphaser

oldphaser

Chief Journeyman
#18
Joined
Sep 8, 2012
Messages
845
#18
Marantz 18 Schematics & Service Bulletins

Here are some schematics & service bulletin obtained of the internet.
The transformer listed as T1 indicates a part number of 52-1000.

The model 19 service manual lists the power transformer T2 as part number 252-1009
https://www.manualslib.com/manual/889073/Marantz-19.html?page=73#manual
https://www.manualslib.com/manual/889073/Marantz-19.html?page=68#manual


View attachment hfe_marantz_model_18_schematics.pdf View attachment hfe_marantz_model_18_service_bulletins.pdf View attachment hfe_marantz_model_18_service_en.pdf
 
Last edited:
C

calman46

Journeyman
#19
Joined
May 9, 2012
Messages
153
Location
MA
#19
This is all great info guys and I appreciate it ,but I have all this .I need to know how to add the CT to the windings. If I was to make this multi- tap winding would add the center wire to the coils as I wound the different windings ? So the center taps would be one wire connected to the center of each winding . Or make separate winding and connect all CT's together . What do you think
 
You must log in or register to reply here.
Top