Performing Alignments

[Beakster]

Hi,

I'd like to be able to do a full alignment as described in the service manual for radios. I have been able to do the current alignment of the finals and driver with my multi-meter but seems like I need some more equipment to do things like receiver alignment properly.

As this is just a hobby and something I won't be doing all the time I'm not going to drop a load of money on expensive hardware so I'm looking to see what can be done relatively cheaply.

It seems like there are 4 things I need: Frequency Counter, Spectrum Analyser, RF Signal Generator, Oscilloscope. This is what I know and some links to devices which I think might work. Any feedback on the suitability of these would be great.

Frequency Counter: There are dedicated frequency counters available fairly cheaply. I assume these should be accurate even though they are cheap due to the way crystals work:
0.1-1100 MHz 0.1- 1.1 GHz Frequency Counter
DC 9-12V 1MHz-1.2GHz RF Frequency Counter

Spectrum Analyser: It seems like some of the new SDR USB dongles can be used as a Spectrum Analyser. They have a range starting at 25MHz and can do all of HF with an up converter:
Nooelec NESDR Smart v4

RF Signal Generator: This one I am not too sure of where to start. Possibly an SDR tranceiver would do it? What are the requirements for a Signal Generator when doing alignments?

Oscilloscope: There are affordable USB oscilloscopes available. The cheaper ones only have 20MHz bandwidth which I'm assuming isn't enough to cover 11 meters. The more expensive ones have 50MHz bandwidth. I understand that USB oscilloscopes tend to be a bit noisy but would this be sufficient?
Hantek 6052BE PC USB Oscilloscope

Also are there any tutorials on the process for doing an alignment on a radio which are a bit more user friendly that the very concise details found in a radio service manual? So far I've found the TRXBench youtube channel very helpful.

Thanks

 

[Big Kahuna]

Other people can chime in on current equipment recommendations but I'll add this.

Unless you are really committed to doing alignments and other testing etc for the long term I just wouldn't recommend going all out. Get a frequency counter and some probes and with that and your multimeter you can do quite a lot. If an old oscilloscope comes up on craigslist then maybe grab it, but be conservative with the cash.

We're heading into a depression/recession and unless you really need that stuff I'm not sure I'd spend the money on it.

I did the same thing as you and had all the gear and then found I didn't use it enough to justify the space or $$$ and ended up selling the majority of it. So really think over how committed you are to doing this stuff and how often you'll be doing it.

I used to love sitting at my desk surrounded by 20-30 radios and equipment but you learn quick can only talk on one at a time.

 

[Robb]

Well, there are other accoutrements needed, such as a 100w dummy load, a reliable watt meter, soldering equipment, a monitor radio. Helpful to have an old computer w/internet to use as reference material (schematics, service manuals, ordering parts, etc, ...). Not to mention a hands-on stock of essential components and old parts radios.

As far as a spectrum analyzer, you can at least monitor with an SDR dongle and a spectrum analyzer program. Again, having a dedicated computer makes this happen. So building a nice PC from not-too-old parts would be advisable, since this will become essential on many levels.

 

[Handy Andy]

As with someone still reeling from the last crash, even now the "cash strapped" need to work more with the tools they already have...

You have a lot of stuff in your possession right now if you only own two radios.

If you can, you can use one radio as your signal generator, AF signal maker, even IF signal tracer - it's all in the radio you can use as your "test subject" - Since you'll be working with CB as a training aid, this method suits better for a person like myself that "discovered" it because I liked the Friends I made by talking to others on the CB.

Try here...
http://gokarters.com/smf/index.php?topic=2330.msg19337#msg19337​

Because you gain the experience from the hands on, and the "needs to know" will come with it as you realize the simplicity of the tools you have versus the requirements of having to buy equipment that will only sit on a shelf once you don't need it or worse, lose interest...

Ok - it's not like that...
​

At lot of times you will only need it to generate signal so you can pipe it into or listen to the other radio as you tune the radio to your "test subject" - a lot of times this is enough to use for your ears are the best tool next to your brain - and since the seem to occupy the same spot in between the shoulders - you're all set...

Read this thread because you will need...

DVM
Test leads
RF - Test leads (they are similar but ISOLATE the signals so you don't cause damage by cross-powering equipment)
Dummy Load
External Speaker
Some simple NON-INDUCTIVE 8 ohm resistors (to measure AF (Audio Frequency)) signals from your radio using the external speaker jack and the resistors are ACROSS the jack output so you can measure VOLUME with your DVM

You have those manuals showing you their test setup - but to really keep it simple, the O-Scope is the LEAST of your worries because it is one of the most Exprn$ive tools that you use only when things get tough.

Frequency Counter helps but then again - if you OWN two or more radios, you have your keystone references in them to use instead of fancy schmantzy graphical and visual tools like SDR dongles...

 

[Robalo]

just get service monitor and you are set plus rms multimeter trust me you save alot money

 

[Robalo]

I still need Rf probe spectrum Analyzer and more knowledge. I got the passion, the patience, and more time now, thanks COVID19 lol.

the radio on the bench is ready, it was the one with High DK watt problem

 

[Low_Boy]

Spectrum analyzer is not a absolutely necessary.

 

[Handy Andy]

A "Spectrum Analyzer" is only going to show the faults within the RF spew coming out of an untuned or UNTRUSTED radio...

Many people think this is the "proof" they need to show their work is correct...

Un huh..."Sure." - she said...

Once the general laughter and hilarity in the roundtable settles down to some casual snickers and an occasional guffaw, someone may be kind enough to play back what you sound like to them...

...it only proves that they watch too many "TV-Detective" shows and use their machine at the "Standalone" proof that their work is done to spec.​

Only thing was, they forgot to mention that the "Ear" of the others that have to listen to what that thing puts out is what matters the most...

Now with the above in mind, you can easily see why there is - or WAS, such a rivalry between Cobra (Dynascan) Uniden, Galaxy (Cybernet) Midland (CTE), Realistic (Defunct) and RCI (Clear Channel) each maker touted theirs to be the best, and with minor tweaks amongst the makers, they are able to weakly stand with their one foot on the banana peel and dance to the beat of their own drum over their claims.

But there were some whom won out in the end by Reputation - of delivering the goods they promised, not necessarily their claims to be the best ones you hear out there.

To be honest, FCC "type-Certified" aside, Galaxy was winning the sales battle because of the "pirate" image they got for Export and Drifts - Fast and Furious or Tokyo Drift aside...

Had to entertain you....​

Ranger made it too, but not after the landscape was littered with the carnage of badly performing bloody messes of radios and their board/network designs - that the makers left behind as their efforts told a story of - "Swell! it works, let's sell it to make enough to cover the R and D for the next ones to be better." - scenario.

Using the above to show example - its' why Galaxy is endeared yet hated by the radio community. It isn't Number One, by some terms - but it's Number One in aspects that many would not like to admit.

So, why did I bring this up? Because you'll have the joy of experiencing - the types of radios you will be working on, you'll find your own favorites amongst the mess - you'll have to work thru it - to make others sound good let alone even work and stay stable.

I USED to like Uniden, but now I happened to enjoy the older styles and flavors of Cobra/Realistic/Midland lines even though their faults and mistakes - even when compared to Midlands' and Realistics' entries into the "Programmable PLL" - rival the level of poor performing quality of vertical cards and edge soldered connections many makes got suckered into thinking this would cheapen their bottom line - it almost cost them their position let alone become ripe for takeover due to the FCC forcing the warranty claim issues with FTC because of the brokenness of the connections and the switchover of soldering from Lead to Lead-free silver - the ductility of one made it favored, but the crystalline of the other, they had to use due to toxicity and poisoning landfill issues.

Uniden - unfortunately - taught me a lesson in futility. Good things don't last forever, and their 6X and 7X series was bad enough with the discrete - the PC and Pro series are nearly extinct now, but the ones they produced in the decades before this, still work and have -outlasted others that were built after their lineage was stopped - from the same company.​

Also, if you didn't notice the Parenthesis - they too "merged" in order to survive in this market - but in every event, each change shows they had trusted one way of production - but the next level brought about several challenges of their own - and they call this "upgrades" and "New and Improved"

You will need to be ready - for the Plethora of "mass-produced" types versus the "lovingly assembled by hand in the USA" that are still around - will show you how little you know now, means you'll have to know a lot more later.

You don't know, what you don't know - until you know.

 

[M0GVZ]

Marconi 2955B Radio Communications Tester and a decent dummy load. Does everything except the spectrum analyser. Even measures AF voltage and SINAD and can generate AF tones at varying voltages too which are three things you failed to mention but need to be able to do.

 

[Beetle]

As with someone still reeling from the last crash, even now the "cash strapped" need to work more with the tools they already have...

You have a lot of stuff in your possession right now if you only own two radios.

If you can, you can use one radio as your signal generator, AF signal maker, even IF signal tracer - it's all in the radio you can use as your "test subject" - Since you'll be working with CB as a training aid, this method suits better for a person like myself that "discovered" it because I liked the Friends I made by talking to others on the CB.

Try here...
http://gokarters.com/smf/index.php?topic=2330.msg19337#msg19337​

Because you gain the experience from the hands on, and the "needs to know" will come with it as you realize the simplicity of the tools you have versus the requirements of having to buy equipment that will only sit on a shelf once you don't need it or worse, lose interest...

View attachment 36690
Ok - it's not like that...
​

At lot of times you will only need it to generate signal so you can pipe it into or listen to the other radio as you tune the radio to your "test subject" - a lot of times this is enough to use for your ears are the best tool next to your brain - and since the seem to occupy the same spot in between the shoulders - you're all set...

Read this thread because you will need...

DVM
Test leads
RF - Test leads (they are similar but ISOLATE the signals so you don't cause damage by cross-powering equipment)
Dummy Load
External Speaker
Some simple NON-INDUCTIVE 8 ohm resistors (to measure AF (Audio Frequency)) signals from your radio using the external speaker jack and the resistors are ACROSS the jack output so you can measure VOLUME with your DVM

You have those manuals showing you their test setup - but to really keep it simple, the O-Scope is the LEAST of your worries because it is one of the most Exprn$ive tools that you use only when things get tough.

Frequency Counter helps but then again - if you OWN two or more radios, you have your keystone references in them to use instead of fancy schmantzy graphical and visual tools like SDR dongles...

Wot 'ump?, says Eyegor

 

[Dmans]

Marconi 2955B Radio Communications Tester

Cost prohibitive for a hobbyist.
Damn nice piece of gear!

73
David

 

[M0GVZ]

Cost prohibitive for a hobbyist.

Not really. They're quite an old bit of kit, the model As are 30 years old. Here in the UK they're going for £300-£500 on the used market, you'll spend more than that buying all the individual gear you need to do the job.

 

[guitar_199]

If I might offer.....

This links is to what has become a favorite of mine to browse through now and then. It is a Ham-centric site and it is primarily like a "want ads". If you get there ... look lower right there is a link for test equipment. There is often TONS of stuff in there for reasonable prices. Good hunting!

(edited to put in the stinking LINK!!!! )
https://swap.qth.com/index.php

Hi,

I'd like to be able to do a full alignment as described in the service manual for radios. I have been able to do the current alignment of the finals and driver with my multi-meter but seems like I need some more equipment to do things like receiver alignment properly.

 

[Beetle]

Just because you have the instruments you need, don't forget you also have to know how to use them properly, AND you have to have some way of knowing if what they're telling you is reasonable: calibration.

 

[Cutlass327]

As with someone still reeling from the last crash, even now the "cash strapped" need to work more with the tools they already have...

You have a lot of stuff in your possession right now if you only own two radios.

If you can, you can use one radio as your signal generator, AF signal maker, even IF signal tracer - it's all in the radio you can use as your "test subject" - Since you'll be working with CB as a training aid, this method suits better for a person like myself that "discovered" it because I liked the Friends I made by talking to others on the CB.

Try here...
http://gokarters.com/smf/index.php?topic=2330.msg19337#msg19337​

Because you gain the experience from the hands on, and the "needs to know" will come with it as you realize the simplicity of the tools you have versus the requirements of having to buy equipment that will only sit on a shelf once you don't need it or worse, lose interest...

View attachment 36690
Ok - it's not like that...
​

At lot of times you will only need it to generate signal so you can pipe it into or listen to the other radio as you tune the radio to your "test subject" - a lot of times this is enough to use for your ears are the best tool next to your brain - and since the seem to occupy the same spot in between the shoulders - you're all set...

Read this thread because you will need...

DVM
Test leads
RF - Test leads (they are similar but ISOLATE the signals so you don't cause damage by cross-powering equipment)
Dummy Load
External Speaker
Some simple NON-INDUCTIVE 8 ohm resistors (to measure AF (Audio Frequency)) signals from your radio using the external speaker jack and the resistors are ACROSS the jack output so you can measure VOLUME with your DVM

You have those manuals showing you their test setup - but to really keep it simple, the O-Scope is the LEAST of your worries because it is one of the most Exprn$ive tools that you use only when things get tough.

Frequency Counter helps but then again - if you OWN two or more radios, you have your keystone references in them to use instead of fancy schmantzy graphical and visual tools like SDR dongles...

In that link, it shows a homebrew RF sampler box. I read someone said to just use the unused port of a coax switch. I connected my oscope like that, and it seems to be picking up output.

Now, is it possible to pipe audio in thru the mic jack from an audio device? I'm building a mix switch box, and if I put an "aux in" jack into it, maybe a couple ceramic caps to isolate the input of DC, could this be used for the 1kHz used for adjusting ALC and such?