Thanks for the fine artwork, Tony!

...and thanks for the parts link, Blustar!

dennis

Took the part Tony sent me (thanks again, Tony )...to an electronics shop in town...the guy has done electronic repairs on keyboards and organs etc. in the area for years...went to put the pot. in...looked good except the threaded shaft for the hex nut was too big for the hole...durnnit...we almost had it!! So sent an e-mail to the link Blustar sent me...(any more goodies in your parts box, Tony?? )...Tom (the repair guy) wrote down: "5k audio taper double pole single throw switch" if that helps. The one Tony sent would work fine if the threaded part was thinner, he said!!

Thanks all

dennis

So close! I'd be tempted to ream the hole larger, file down the control's thread a mite and squeeze it in. But that's me and brute force is just one of my relied on tools.

There's bound to be the correct control and would be the easier and less-invasive way to go. At least you found a competent tech and it's on the bench!

The old control must be out, so maybe get a good pic to help find its brother.

-Ed

I thought that might happen and I would ream the hole too, but that's just me. Most controls that you find are going to be 3/8 bushing. I have some with the smaller bushing but not with two switches. The correct control for that radio is more like 10K by the way. 5K is low but will likely be OK in that particular circuit.

Sorry it didn't work out.

Tony

Oops...forgot where to post this!!...finally got the AF/Gain switch fixed on the 150-A!!...picked up some AM, but next is an antenna, probably some indoor type...just wire maybe!...rest of the knobs ar smooth and the lights even work!! I do have it plugged in near my computer...that might not be good for reception??
Hello everyone, and thanks for all the ideas and input!

dennis

Hi everyone!...haven't been on for a while. Got the DX-150a fired up..just a wire antenna hooked to terminal A for the time being. Picked up a few stations, and a ham or two. There is a plug in back near the terminals I would assume is for an antenna jack of some type...any ideas on that?...and antenna length/gauge?

thanks, dennis

A picture in the manual doesn't show a "plug" near the antenna terminals. Perhaps your set has some kind of user modification. Also, when using a single wire antenna connected to terminal A1, you need to connect a jumper between terminals A2 and GND for best performance.

Here is a PDF of the user manual if you don't already have it.

http://pdf.textfiles.com/manuals/SCANNE ... Manual.pdf

Dave

Thanks Dave!
It looks like a coax connector mounted right under the terminals...has a small hole in center smaller than a 1/8 connector. I've seen them mounted on the DXs now and then on EBay. I'll try and post a picture. ..and thanks for the pdf!

dennis

Hi Dennis,

Good to read you still have the DX-150a and it's working for you. You should receive more than a few stations, especially on BCB AM.

Chances are a previous owner added a jack for his style of antenna connector. Easy to verify by popping the bottom cover and tracing the wires. If they just go to the screw terminals or connect to the same place on the circuit board, there you have it. Hopefully they left the screw terminals also connected, but if you're only hearing a "few" stations, they may have just moved the wires to the new connector and abandoned the screw terminals. Do you notice an increase in signal by adding some wire to the screw? If you don't happen to have the connector to plug into the added jack, chances are Radio Shack carries it, but you can just stab a wire into the center conductor of the jack to check it.

On mine, I run a short wire from the antenna terminal to the front of the set with an alligator clip on it, so I can clip any wire I wish onto it without having to move the radio and all the junk I have stacked on top.

Also on mine, the internal speaker was toast. I installed a replacement, but prefer listening through an external speaker that has a bit better fidelity and faces front instead of to the side.

There are also modifications to add a digital frequency display, so that's another possibility for your mystery jack, though not as likely.

I think on my DX-150, it does as well with a single wire, and leaving A2 and GND open. Try it both ways, you can't hurt anything. Also try a wire to GND that goes to a good earth ground.

You need to peak the ANTenna Trim control on the front as you change bands or tune around. It can make a big difference sometimes. I run the RF gain at the 2 o'clock position or higher.

Many SW stations are very crowded, especially on the ham portions. If you use only the main tuning knob, you can fly right by signals unless you really creep the knob. The bandspread is good for fine-tuning these crowded portions of the bands. You don't really need to worry about its position unless you're trying to calibrate it to determine the frequency of a station you hear. On the DX series, just getting a close guess of the frequency is about par for the course. I can aim for a station just by its frequency and usually nail it, but it's much harder to determine a ham's precise frequency with much accuracy.

Mine sees duty nearly every evening, even if it's only parked on a favorite AM station for background noise.

-Ed

Thanks for all the info, Ed!...I'm missing one terminal screw in the back...any idea what thread it is??...I can always match one at the local hdwe store. Being on the West coast is supposed to be one of the poorest dx reception areas from what I've heard...but still want to get a decent antenna for the old beast

If the set works better when leaving A2 open, one or both of the protection diodes may be shorted. With my similar DX-160, signals increase significantly when the jumper is in place.



Dave

This got me to wondering about that shortinbg link. I knew I'd posted about it a long time ago, but lost the link to the thread. It oughta be made a sticky, since it's worthwhile to refer to regarding the DX-150 and DX-160 receivers.

Here's the link to the 2006 thread on the DX-series: http://www.antiqueradios.com/forums/vie ... =4&t=57958

Owing to that thread, I purchased both a DX-150 and DX-160, but sold the 160 after awhile. It turns out it was on the 160 that I noticed a loss of reception with the shorting link installed. Long enough ago that I remembered the issue but had forgotten the details.

Here's what I posted back then and Dave's reply:





So I'm glad to see there's a reason why! Being lazy, I didn't bother to remove the overburden to pull out my DX-150 to see the back and recall how I had my antenna connected. I just clip my antenna to my cheater alligator clip and never see the back of it for months on end!

-Ed

What, no junk box? If it's the antenna screw, just rob one of the others for now or use it to find a match.

Any hank of wire will do for now. Some people like using metal Slinky spring-toys. For me, old speaker wire, enameled wire, power cords I cut off of dead lamps. Anything "conductive." Tie that to a bedspring, steel cabinet, metal window frame. Or toss it out a window into a tree. Or tie to a metal fence.

You can spend a lot of time and energy designing and installing the perfect antenna. With no basis for comparison, how well might it work? If you first erect the most simple antenna possible, it gives you a basis of comparison to see if that whiz-bang jobbie is any better. You can have a wire strung in minutes and start trying it out. String up another, then connect it in place of the prior one. Now you have two to compare.

Funny thing is, the fancy one might be better at some frequencies, while the 'ol hank of wire on the floor or in the tree is actually superior on others!

Many of us have multiple wires strung about to choose from or to use on several radios at once. Too many people fret about the details, when the important thing is to just add on some wire and start playing around.

-Ed

Good advice on antennas!

The diodes across the antenna terminals are listed in the schematic as 1N34. I can't think of a worse type to use as protection diodes. I think any large signal like a lightning strike miles away would cause these to short. I think they are there to protect the FET RF amp from overload.

Dave

Distant lightning strike or looking at them funny! That will provide no protection at all.

Brett

Thanks for all the input, guys!

The jack looks to be a coax/bnc connector..(with my limited knowledge) from what I've seen on other radios and connectors online...I'll try to send a pic of the back, so maybe get some more suggestions. I just have an indoor wire coming out of this jack...(female input on it...) with B and ground connected...maybe 20-25 feet. I'm sure an outdoor wire would help. I pick up a couple of strong stations here and there at night...Havana, BBC, and the time signals

dennis

That seems kinda quiet. You should pick up a few internationals and for sure the religious blowtorches. Is your RF gain maxed? Tune in on any station or even just band noise and peak the antenna trimmer for highest sound level. Turn up the audio level until you hear some background hiss or static. Now tune very slowly and you should be able to pick up a few faint signals. Be ready for a blowtorch to come blasting through when you have the gain set this high. I ride one hand on the volume or rf gains and the other hand on tuning or bandspread to be ready for abrupt changes in signal strength, especially at night when wifey is trying to sleep!

AM BCB uses the built-in rod, but the external is coupled in too. SW bands use only the real panel connection. Add more wire if everything else seems ok.

It won't hurt a thing to just touch your antenna wire to any of the various antenna lead-in connections. Just attach it to the one that works best. It sounds like you have the correct plug that fits the BNC to hook your wire onto, so you should be good to go. Maybe check continuity with a multimeter, sometimes the wires aren't making good contact inside the jack or plug itself, especially if it's a "scrounged" plug that may have been bad, cut off and not tossed. Lacking a "proper" connector to the BNC or whatever is not a deal-breaker. Just insert any piece of wire, nail, whatever, into the center that fits snugly and wrap or hook your antenna onto that. Buy a more proper connector when you get around to it.

Sure, it may or may not be matched for best reception, but chances are it wasn't to begin with. Probably it's just an aftermarket connector tagged onto or replacing the screw terminals. Opening up the bottom and having a looksee will answer that, but if you get a method that works as-is, you're in business!

-Ed

Thanks Ed!

I'll get some pics of the guts when I find my camera here somewhere...hope you guys don't mind a bonehead like me fuddling his way with stuff here...always had the interest in SW listening, and now a little more time, but not necessarily more brains

I also just snagged a Panasonic RF-3100 on Ebay that should be on it's way soon, not sure if that fits any category on this forum, but I still won't give up on the 150!

dennis

I'd be interested to hear what you think about the RF-3100. You are welcome to start a new thread here about it when it arrives.

Dave

I will, Dave

The 150 seems to be dead on band D AM all of a sudden...even with AF and RF gains full throttle and turning the ant trim...I get static on SSB on band D, though.