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Radio Alignment
#1

Hi All
I am looking for some help on alignment of a radio. I have never attempted to do this.The only test equipment I have is a Fluke Digital Display multimeter. It dose have a Bar graph with fast response. So I guess the help I need is what kind of equipment do I need to align a radio. Can this be gotten at a reasonable cost? Also is there any good books on alignment and trouble shooting? Is it hard to learn? There is an old guy (my age Icon_razz ) in town that dose this, but the cost is high.
Thanks In Advance
Bob
#2

Bob

The download schematics from http://www.nostalgiaair.org usually have a page of alignment instructions. If not you can usually get help here on the Phorum.

I would suggest as minimum a signal generator. I have an EICO 324 which is adequate for antique broadcast radio alignment. You may be able to find one on Ebay or a local ham fest.

Hope this helps.
nv3g
Oscar
#3

This site: http://antiqueradios.com/archive.shtml has pdf copies of Elements of Radio Servicing you can download for free. Chapter 22, page 428, covers generic alignment quite well. About the only thing you need is a signal generator, as Oscar says, and the schematic and parts locations for the radio you are working on.

Riders pages usually have alignment instructions for specific radios, but for a simple radio you don't really need them.

Alignment for AM and Short Wave is pretty simple. There are three steps, usually:

1) Adjust the capacitors and/or cores on the IF transformers to exactly 455 KHz (or whatever the IF frequency your radio is set to--usually on the schematic.) -- use a signal generator

2) Adjust any antenna trimmers for greatest throughput -- use any radio station or a signal generator

3) Adjust the tuning to align the dial pointer with the numbers on the dial. Works best with a signal generator or you can use two radio stations at the high and low ends of the band.

If you have a multi-band radio you may need to repeat steps 2 and 3 with each band. FM is different. I've never aligned one, so I can't tell you anything about it. My signal generator has a generic procedure for aligning FM.

John Honeycutt
#4

I have an ancient Superior Instruments Genometer Signal Generator, which for it's age is pretty accurate. An old Heathkit or Eico would do as well, I usually follow the instructions in the Rider's manuals for the IF alignment, but if I have no schematic, I use a piece of styfrofoam about 2X3 inches upon which I have wound about 12 turns of #20 wire from an old transformer, and I couple that to the 600 cps modulated output of the generator and place it near the loop of the radio for RF alignment. The idea here is to get the radio to listen to the signal generator.

If I have no instructions I couple the signal generator to the ground and the first IF grid (both sides with a .1 mfd 630 volt capacitor so I continue to live, and so does the set I am working on,) and do the second section output, first section output, second section input, first section input in that order whilst keeping a digital meter across the voice coil to peak the response. You can do this by ear, if you can still reliably hear. The louder the better. That is with the tuning capacitor shut down to it's lowest level and the signal generator set to the IF frequency, usually 455 or 456 KC, but sometimes half that value, depending on the model. And I found out that as long as you are close, it doesn't ake a dime's worth of diference if you are off by a KC or two, but I still would like to have a meter to verify the output of the signal generator, and if anyone has a spare, please let me know. Please, not a boat anchor with nixie tubes, although it would be neat.

Tell us what came next!
#5

Hello
Want to thank you for the help. I now have an EICO324 signal generator that I got off of ebay. I didn't get any manuals, or leads. The leads I can make. I think it is good, because I can set a radio to a station and tune the generator to that RF and hear it on the radio.
Is this a good check? I noticed that there are slugs for each range. What would I need to calibrate this? I think I'll look around the internet to see if I can find a manual for it.
The web site that Raleigh put up is nice. They have a file for the book "Elements of radio servicing" that has a lot of good stuff for a rookie. Another question is do I need to get a tube tester? If so what is a good one?
Codefox1 mentioned Nixie tubes. They are old, back in the early sixties I worked on NC machine tools that used nixie tube read outs. I don't have any to send to him!!!
Bob
#6

You can find the Eico 324 manuals and info here.
http://bama.edebris.com/manuals/eico/
#7

Bob,
I had to go thru your posts to deterime what radio this is. Can I assume you're still working on the 40-190? The pushbutton tuning is similiar to the 1940 RCA 19K I'm rewiring now. Both have switchable coils and trimmers that tune a certain range. It appears the setup was intended to be done by the local dealer who would insert station call letters by the push buttons and tune the presets before the set went out the door. It sounds like you're at that point when you set your RF generator to a station and can hear it over the radio. Try it using the pushbuttons instead of the dial. The Rider directions say to tune the osc first, detune the RF gen and then peak the osc and ant until the station is tuned in. I assume osc is the coil and ant is the trimmer. Remember that buttons 1, 2, and 3 tune 540-1060; 4 and 5 tune 650-1110; and 6 and 7 tune 920-1600.
I think Codefox was asking for a spare meter built after the nixie tube era.

Dave
Colo Spgs
#8

You're right. I am a kind of belt and suspenders person. I'd just like to know if my signal generator is really putting out what it says on the dial. A tiny amount of tweaking during alignment makes a big difference in the sensitivity and selectivity on these sets. Forty years ago the old behemoths sat in the lab at university. They were never turned off after they were calibrated until they failed. Deadly accurate and housed in a glass house next to the glass house with the computer - which was manned by techs with white coats who would, when they got around to it, process your punch card programs and give you, maybe 15 seconds on the box before sending it back by interoffice mail along with the printed good or bad news from running the algol program.
#9

Hello
I want to let exray know that web site he posted is great. I was able to print a complete manual for my EICO324. It has calibration instructions. So I am going to give that a try. It should not be to bad because, as I said it sounded like it was close. I paid a guy from town, to do the alignment on my 40-190. But I want to continue doing this, so thats why I decided to get some equipment. The first thing I'll try is to change a couple of the presets on the 40-190. I have a 1947 Crosley floor model that is ready for alignment. So I am going to attempt it. Hope it isn't over my head because it has AM,FM and SW. The one I am working on now is a 1934 Crosley Tombstone that I got 40 years ago from my grandma. I have it totally stripped down, but using the help from this Phorum I think I can get it back together.
Once again Thanks for the help.
Later
Bob
#10

Hello Bob. The best way to make sure your RF Gen is producing a accurate signal, is by attaching its leads to another test meter called a "frequency counter" for spot-on accuracy. Since not everyone has a freq-counter onhand, another good source to determine if your RF gen is producing a accurate signal, is to use a portable multi-band battery powered Radio near it that has a digital push-button type tuner that uses standardized crystals for all Bands various frequencys. These type digital tuning type portable radios usually cover ther entire AM, SW, & FM Bands. Can find them cheap sometimes at garage-sales, pawn shops, etc!
You will hear the "harmonics" generated by your RF gen, and be able to adjust the accuracy of the output by monitoring the harmonics into the portable digital "crystal" receiver which is spot-on itself for accuracy of tuning! These small handheld digital-tuning receivers are much less expensive than purchasing a good quality digital "frequency-counter" bench test item, and are also a great workbench item to listen too while your restoring vintage radios, and then can be used as a "accurate" RF gen monitoring tool also!! IE:, the 1st harmonic of 455 kc, is 910 kc on the portable radios (highly accurate crystal digital tuner) AM dial. Then, you know your injecting a proper 455 kc from your vintage RF gen, by monitoring by ear, all across the dial, for any freqs you choose to "align" on any Band. Just trying to help. Best of luck with all your restorations!!
#11

I am wanting to align my beautiful Philco 40-190. It plays and I have a good signal generator (probably 1970s model). My problem is determining where to hook up the signal output. I have the schematic and Riders alignment instructions but they are unclear. Adjusting the I.F.s went fine and the instructions say hook to No. 1 on Loop Panel. That worked great.

From there on it simply says for Output Connections: Use Loop on Generator. I read the part about making a wire loop in the generator output lead, but it doesn't say where to attach it for the next five adjustments, including SW. Anybody have a handle on correct placement of the lead?

Your advice will be appreciated. Thanks.
#12

Guys,
search You Tube for AM radio Alignment. There are quite a few videos that will show you how to align these radios.

Good luck,
Eric




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