Oscilloscope Help

[Blazeorange]

Hey: I've been toying with picking up some service equipment to learn on and progress my radio knowledge a little further.

I was looking for a Motorola:

Motorola Dual Trace Oscilloscope (R1004 A),
Motorola Service Monitor (R1200 A),
Bird 6104 wattmeter (0-2 Watt and 0-10 watt Scales),
Motorola two-tone signal generator (S1333B),
Motorola low frequency counter (S1357A),
Motorola bench power supply capable to go 0 to 20 VDC, (S1347 or S1348).

I was also looking for a wattmeter (not brand specific) for the mobile radios. Any suggestions.

Predominantly the majority of stuff I want to work with is portables on up to 110 Watt Mobiles.

What range Oscilloscope should I be looking for (Most of the frequencies I deal with seem to center around 155 MHz.)

Now I'm basing this search list out of an MT-500 Service Guide for suggested equipment. There were some other items listed that I've already located on E-Bay. Now I know that this manual is plenty old so any substitute equipment suggestions would be great. I'm not brand specific.

Any techs or knowledgeable folks who can point me in the right direction would be appreciated. Don't worry, I don't plan to put anyone out of a job. This is for my own personal quest for knowledge and better understanding of radios.

[elkbow]

Hey: I've been toying with picking up some service equipment to learn on and progress my radio knowledge a little further.

I was looking for a Motorola:

Motorola Dual Trace Oscilloscope (R1004 A),
Motorola Service Monitor (R1200 A),
Bird 6104 wattmeter (0-2 Watt and 0-10 watt Scales),
Motorola two-tone signal generator (S1333B),
Motorola low frequency counter (S1357A),
Motorola bench power supply capable to go 0 to 20 VDC, (S1347 or S1348).

I was also looking for a wattmeter (not brand specific) for the mobile radios. Any suggestions.

Predominantly the majority of stuff I want to work with is portables on up to 110 Watt Mobiles.

What range Oscilloscope should I be looking for (Most of the frequencies I deal with seem to center around 155 MHz.)

Now I'm basing this search list out of an MT-500 Service Guide for suggested equipment. There were some other items listed that I've already located on E-Bay. Now I know that this manual is plenty old so any substitute equipment suggestions would be great. I'm not brand specific.

Any techs or knowledgeable folks who can point me in the right direction would be appreciated. Don't worry, I don't plan to put anyone out of a job. This is for my own personal quest for knowledge and better understanding of radios.

If you buy the right service monitor, basically everything you listed will be provided in the service monitor...i.e. wattmeter, oscope, tone generator, frequency counter, etc.

The one thing that won't be is the Power Supply. In order to power mobile radio's on the bench, I have an Astron RS-70M, can easily handle my 110 Watt Spectra's. The other thing you will probably need is an attenuator that can handle your frequency range of your radio's and attenuate the power input of your radio's. My IFR-1600S can only handle 50 Watts continuous, with 200W momentary.

Now having the other equipment as an additional measurement tool to verify your service monitor is nice. I still have a Bird 43 Thruline wattmeter, I also have a HP 300Mhz digitizing Oscope. I have a bench power supply, which is a Sorensen/Power Ten Variable supply, 0-40V/0-25A.....

Just something to think about....many ways to go here....

[Susan157]

If you are serious in servicing radios||


Well like what was just said .

Buy the all in one service monitor.

They sell them at Dayton Ohio.

Hamvention 2004

http://www.hamvention.org

Soar with the Eagles

Don.t waste your money on turkeys.

.

[Blazeorange]

I agree that it would be nice but I haven't been able to find an affordable one that I can justify for "hobby."

I still need an answer on my dual trace oscilloscope hunt. If I generally deal with frequencies in the 155 MHz range, what range Oscilloscope should I be looking for?

With the variance in cost for service monitors, I'm going to build my test bench, piece by piece.

I think a frequency counter and an oscilloscope are next on the list.

Thanks in advance.

Blaze.

[N4UMJ]

Hey Blazeorange,

Buying the seperate boxes instead of a service monitor worked for me but it is not very portable at all. My start in communications was working the VHF Communications Avionics Bench in a commercial airline avionics shop and they relied heavily on the seperate box approach so it was very familiar to me.

I think you will find the pre-ATE (automated test equipment) type test equipment to be the most affordable as it leaves off the more expensive GPIB port which can add to the complexity and cost.

I guess the question that you may want to ask yourself is will you be branching out working on other radios in the future besides the MT500? For me the majority of my work is on the Saber line right now. Technology goes forward and as the complexity increases so will the needed test equipment. Each tech has needs unique to their situation.

Briefly here is what I am using on my workbench:

* Tektronix 475 200 MHz scope (1980's maybe --not sure?) and it still hums along just fine. Scope probes are not cheap either.

* Optoelectronics Frequency Counter Model 3000+

* Bird 6154 Termaline Wattmeter 25-1300MHz (5-15-50-150W).

* Marconi TF2304 Deviation/Modulation Meter

* Motorola R1151 Tone generator

* HP 3312A Function Generator.

* HP8654B AM/FM +10/-120 dBm 10-520 MHz RF Signal Generator

* Helper Sinadder 3 for RX sensitivity checks.

Add to all that a decent voltmeter (I am using a Fluke 87) and the necessary probes for it (RF Probe by Fluke) and plenty of BNC to BNC jumper cables.

I found some items on eBay and I did have to be sort of selective and wait for the better condition equipment to show up. Other equipment I have found at Hamfests/Swapmeets. Be prepared to repair the older stuff and find manuals for them as well. This really is the negative because so much is sold "as is" and some will have problems/issues.

Right now looking back the Service Monitor route would have been best for me but as I saw things I needed and priced right I acquired them. Being a Ham I already had some basic test equipment.

I did look at the IFR500A and the Marconi 2955 Service Monitors very closely.

Don't overlook local Hamfests for deals too but most surplus test equipment vendors seem to be centering more around the internet
sales. Dayton would be an exception but its been years since I have attended it.

Forgot to mention I also use my Icom R8500 100kHz to 2 Ghz receiver for over the air checks and troubleshooting. Also use an Optoelectronics DC440 Tone reader hooked into the discriminator of it for DTMF/CTCSS and DCS decoding.

As you can tell this stuff adds up $$ and I admit I probably have way too much invested in it for the little work that I have done with it. Return on investment is not even close!

Thanks for bringing up this topic as it was one I wanted to mention months back.

Eddie
N4UMJ

[N4UMJ]

One more thing here is a neat link relating to Oscilloscope Bandwidth that I ran across months back......

http://www.tek.com/Measurement/cgi-bin/ ... illoscopes

Eddie

[kmoose]

The first question I have is: What are you going to be using the O'scope to look at? If you want to look at RF, then maybe you would be better off buying a decent used Spectrum Analyzer. If you are just going to be looking at audio and IF signals, then just about any relatively inexpensive 100 Mhz o'scope should work fine for you. I may be wrong here, but I think most techs who are looking at RF (the FM type, anyway) with an o'scope will tell you that they only use the scope to verify the presence of said RF, and to make sure the amplifier(s) give them gain of some sort.