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RAA1 AM Antenna question

Pio1980 said:
Got it downloaded and opened, no useful tech info or diagram for the AM antenna box.
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As @Classic_CJ and @MACKIE1975 suggested, look here
http://akdatabase.com/AKview/albums/userpics/10004/MX135 Service.pdf
Page 66

Schematic and circuit board layout. The schematic vague as to where the ferrite rod is; inside the box?

My ebay purchase should arrive shortly. The MX130 manual shows an AM antenna port on the back. I just have to experiment to find out if the RAA1 uses the MX130 rod or overrides it.
 
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jlovda said:
As @Classic_CJ and @MACKIE1975 suggested, look here
http://akdatabase.com/AKview/albums/userpics/10004/MX135 Service.pdf
Page 66

Schematic and circuit board layout. The schematic vague as to where the ferrite rod is; inside the box?
Click to expand...
Thnx, don't see a diagram for the box, but I deduce from the tuner connections that a tuned amp stage in the box is ghost powered thru the RF line and the ferrite rod loop tuned by varactor diode, with padder and trimmer caps to ensure tune tracking.
 
jlovda said:
As @Classic_CJ and @MACKIE1975 suggested, look here
http://akdatabase.com/AKview/albums/userpics/10004/MX135 Service.pdf
Page 66

Schematic and circuit board layout. The schematic vague as to where the ferrite rod is; inside the box?

My ebay purchase should arrive shortly. The MX130 manual shows an AM antenna port on the back. I just have to experiment to find out if the RAA1 uses the MX130 rod or overrides it.
Click to expand...
I do not see an application for the RAA1 on the MX130 on the rear connections.
 
Pio1980 said:
I do not see an application for the RAA1 on the MX130 on the rear connections.
Click to expand...
Bottom right corner... "AM ANT."

If it doesn't work or is not compatible I will just put it back on ebay. This was an experiment.
 
Pio1980 said:
Thnx, it's possible it overrides the on-board rod, I'd need to see a skiz to confirm. Does the user manual cover this?
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Well, I should have been smart enough to search through the owner's manual before I bought the RAA1. The DIN antenna socket just uses two of the pins; an antenna wire and ground. There is no power going out. The manual just spends about a paragraph telling you how to wrap a wire around a window. The funny thing is that they say nothing about what the DIN looks like, where to buy one, etc. When you read it, the first thing that comes to mind was they just want you to push a wire into the holes. They should have just put push terminals (like an MR73/74) on the back. Whoever laid out the design of the back panel was more interested in having the antenna socket match the two other DIN sockets next to it. It appears the RAA1 is ONLY used on the MX135. At least I learned something about the box.
 
jlovda said:
Well, I should have been smart enough to search through the owner's manual before I bought the RAA1. The DIN antenna socket just uses two of the pins; an antenna wire and ground. There is no power going out. The manual just spends about a paragraph telling you how to wrap a wire around a window. The funny thing is that they say nothing about what the DIN looks like, where to buy one, etc. When you read it, the first thing that comes to mind was they just want you to push a wire into the holes. They should have just put push terminals (like an MR73/74) on the back. Whoever laid out the design of the back panel was more interested in having the antenna socket match the two other DIN sockets next to it. It appears the RAA1 is ONLY used on the MX135. At least I learned something about the box.
Click to expand...
Were you going to use the AM?
 
Pio1980 said:
Were you going to use the AM?
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Silly question. I wouldn't have bothered buying this thing if I wasn't. I have been an AM DXer since high school. It's fun to see what I can pick up. The problem now with the MX130 is that it's jammed up against a wall and it is impossible to move the ferrite rod around.
 
jlovda said:
Silly question. I wouldn't have bothered buying this thing if I wasn't. I have been an AM DXer since high school. It's fun to see what I can pick up. The problem now with the MX130 is that it's jammed up against a wall and it is impossible to move the ferrite rod around.
Click to expand...
I'm thinking maybe coupling a remote tuned helper loop to it. You familiar with the AM helper loops, Select-A-Tenna, Kaito, ect?
 
I've used helper loops on lesser AV receivers with the small wire coil separate AM loops with excellent results.
 
Sorry if I misled anyone re:the MX135 and the RAA1 AM antenna accessory. I just grabbed the service manual out of the file cabinet because I was all-but certain that it used the RAA1. There are others. I just verified these models by checking the service manuals: MX119, MX132, MX134, MX135, MX136, MR85.

There may be other tuners, but I don't have most manuals after the MR7082, which does not utilize the RAA1.

The MR85, BTW, was unusual in that it could be equipped with a second tuner module, allowing for two different stations to be tuned in the one chassis. IIRC, the primary idea there was to serve in multi-room systems, so two people could listen to two different stations, sourced by a single chassis.

~sigh~ Been out of retail for 15 years now, used to have all this stuff in my head!

To jlovda-- What was your main intent with the MX130? You might also pick up a seperate Mac tuner that uses the RAA1 and connect it to the MX130. Plenty of analog inputs on that puppy, for sure. A local dealer I do some service work for occasionally tells me he has customers looking for these early surround units just because of the sheer number of analog inputs, rather than the surround features.
 
The RAA1 was also used in the C45 PreAmp, and the MHT-100 and MHT-200 Home Theater units.

Larry
 
Thanks for all your help. This was just a $42 experiment that turned into a dead end. I'll just sell it back on ebay. I also have a Scott 312-D, Technics ST-G7 and three long distance Zenith portable radios to fiddle with. I don't need to dig any further. I was just curious to see if I could get the performance to improve (for no real reason). Quite frankly, my Zenith R-3000, R-2000 and R-500H portable radios from about 1959-1962 are the best performers for long distance AM.

I'm finished.

At least this thread helped pull some mystery out of the RAA1. We now have a good idea how it works, what's in it and what tuners it is compatible with.
 
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