Help me hook up my antenna TM-1001

[jbpollock]

The Realistic TM-1001 tuner is supposed to have built in AM (the bar) and FM (the power cord as seen in the picture?) antennas, but I live in a small valley which has proven to reduce signals in some areas of the house.

I bought a powered FM/AM antenna in an attempt to improve reception, but now I don't know how to hook it up. The AM connection consists of 2 wires, but as you can see below there is only one AM antenna terminal. Secondly, the FM portion is coaxial style but comes with a 75 ohm to 75 ohm (not 75 to 300 ohm) converter that also converts it to 2 wires. However, I have no idea what the 75 ohm terminal on the back of this is designed for. It is the terminal on the right that consists of a metal loop with a screw below it. There are two 300 ohm terminals, but I assume this isn't the correct spot to connect since the converter is 75 to 75 ohms.

Any advice is appreciated!

 

[hpsenicka]

You didn't specify in your post, but presumably your antenna has a 75 ohm coax connection?

[Edit: you did state that the antenna provides a 75ohm connection with 2 spade-type terminals... these can be attached to the 75 ohm terminals on the back of the receiver as MarkW described in his post...]


If thats the case you have the following options:

1. Buy a 75-300 Ohm balun/adapter that will convert the coax lead from your antenna to 2 wire spade terminal connection that will connect to the 300 ohm leads on your tuner.

2. The peculiar looking 75 Ohm connection provided on the back of your tuner is designed to accomodate a coax cable without a crimped on F-type connector. You can cut the connector off your antenna lead, but I would instead suggest that you find/purchase a short length of coax cable and a union/coupler fitting. Using the coupler, attach one end of the coax to the antenna lead. Take the other end and cut off the screw on F-type fitting, expose a suitable length of the center lead and peel back about an inch of the outer insulation jacket to expose the sheilding. Trim to length so that the center lead will reach the terminal screw with the exposed sheilding fitting under the "clamp" bracket.

 

[Markw]

You might want to use that 75 > 75 ohm connector by connecting one lead (inside wire?) to the screw on the bottom and the other lead (shield?) to one of the screws on the "U" shaped clamp above it.

As far as AM goes, well, AM antennas are generally a single long wire so they really only use one terminal. Experiment here but don't expect miracles.

 

[jbpollock]

Thanks for the responses guys. I hooked the tuner up with the FM portion of the antenna attached to the 75 ohm bracket as described by Mark and didn't get a real noticeable improvement. I also tried the 75-300 ohm converstion as suggested by hpsenicka and again didn't get a marked improvement.

I attached the AM leads, one to the AM terminal and grounded the other to the chasis of the tuner. Again, I couldn't tell a difference in AM reception compared with just using the built in antenna.

I am starting to think that this old tuner is possibly out of spec and in need of repair. I haven't hooked it up to my bedroom system to directly compare its performance to the MCS-3701 tuner in there, but I have plugged it in in the room. Based on watching the meters and the stereo light, it doesn't seem to pull in stations as well even though it should easily best the MCS.

Thanks again for the advise. Hopefully I will figure out a solution and this isn't a case of a sick tuner.

 

[Markw]

Don't give up hope on the tuner quite yet.

I have very little faith in tiny indoor amplified antennas. Give it a shot with a real antenna before condeming it to the scrap heap. That TM-1001 is really a pretty good tuner.

I've always said that I'd rather have a poor tuner with a good antenna than a good tuner with a poor antenna.

that said, I hope ypu can get your money back on that powered antenna and try one of RatShack's little $4.00 300 ohm dipole antennas. You'll be better off.

 

[jbpollock]

I think I will probably take it back. It was a 30 dollar Terk from Circuit City. Thought it might be worth a shot. I have, however, been fairly happy with the Archer (Radio Shack) amplifed FM antenna in the bedroom system.

 

[Brian]

For AM, besides the antenna run, you need to run a wire from the ground to an earth ground. You could run a wire from the U shaped clamp to the screw of the AC outlet cover provided you have a ground wire on the electrical box. Most tuners provide a terminal for the ground.

 

[jbpollock]

Well, it turns out that the TM-1001 works just fine and I am listening to it right now. All it needed was the 4.95 dipole antenna from Radio Shack instead of the fancy Terk powered antenna. Its a great sounding tuner, btw. Thanks for all of the advice. Looks like Circuit City will have an open box Terk or sale after I retun it if anyone is interested

I will try the grounding trick on the AM antenna next. It receives stations fairly well....just the usual interferece with other statiion at this point.

 

[vintagestereo]

Just picked up a TM-1001 curbside earlier today. Anyone know anything about it?

-- Chris

 

[Manitoulin]

Boy, Chris you sure are cross posting a lot about this tuner.

 

[Paul C]

For AM, a "loop" type is best. I am having GREAT success with an untuned loop like this:

http://members.cox.net/rwagoner/columns/am_antenna.html

I bought a kit of the same antenna, but will be glad to give you measurements if you want to make your own.

The upright and crossbar are 1/2" x 3/4" pine, notched in the middle, attached with a brass bolt and nut (non-inductive). On each corner is a brass "shoulder hook", sort of like a cup hook, but straight. Just four turns of 22 ga insulated wire and a terminal. the base is really just a decopage plaque from a craft store. I stained and varnished (some poly waterbased stuff that dries in 30 minutes, Minwax). Connected with twinlead to the ground and AM terminals on my receiver. At night I get stations from all over the mid USA, one is nearly 1000 miles away. Local and regional stations during the day are so clean they sound like FM. See:

http://audiokarma.org/forums/showthread.php?t=64918&page=3&pp=15

You don't have to put up with mediocre AM reception.

 

[Paul C]

For FM...

I assume you have four terminals on back, as do many receivers:

* -300 ohm- * -75ohm - *(ground) * (AM)

There are two terminals labeled 300 ohm. You may connect 300 ohm "twinlead" between these two posts. You may also connect the two leads from a 75 ohm to 300 ohm transformer, aka "balun" to the two 300 ohm terminals.

For 75 ohm, you may connect the center lead of 75 ohm (RG6 or RG58) cable to the terminal labeled 75 ohm (which is also one of the two 300 ohm terminals). The shield of the cable connects to the ground terminal. In this configuration no transformer is used, and a better signal may be obtained. There is some loss in a transformer or balun.

Back to AM:

An AM Loop goes to the two terminals on the right, labeled ground and AM.

Some will suggest a longwire. Do you know how long is needed for AM? For a quarter wave longwire, from 48 feet (1600 khz) to 144 feet (540 khz) to cover the AM band. This is just not practical. A loop, which works on magnetic induction, is the only practical solution for AM. Terk, C. Crane, and a few others make nice tunable loops. make sure you get one that has terminals or jack to connect to your tuner or receiver. Some don't, and are intended for a portable radio with built in antenna to be placed beside the tuned loop antenna. So, chose carefully.

The twinlead diapole is not very good. I have had better success with a 5' (60") piece of hookup wire stretched out. 60" is 1/4 wave right in the middle of the FM band. A 1/4 wave would be from about 63" for the lower end of the band to about 57" for the upper end. 60" will cover the whole FM band well. Attach this piece of wire to whichever FM terminal gives better results. Usually both work well. You may connect one 60" piece to one of the 300 ohm terminals, and another 60" piece to the other terminal.

But this is for easy and quick hookup. I have a Godar FM1-A in the attic connected to my main tuner with RG6 cable. My other receivers have just the 60" wire. I have the "Ultimate Loop" on all for AM.

Even better for FM, I used to have a Channel Master TV antenna. I don't remember the model. It was on a mast about 10' above the peak of the roof. It worked very well, but I lost it in a storm years ago. The FM antenna from Radio Shack (actually Antennacraft FM6) gets very good reviews, though I have not tried it. It is made specifically for FM band, so it should work better than the TV antenna I had before.

If you already have a TV antenna, try that. FM band is sandwiched between TV channel 6 and channel 7, right in the middle of the TV VHF band.

Some cable TV services provide local and regional FM stations on their service. You may be able to simply use a "splitter" and tap off your TV cable.