The AM Forum

After making my own Scope pickup and trying several different ways to hook up my Gates and Scope, I broke down and purchased The AM5K.

This thing is the best I have used for one simple reason. The Trigger now works on the scope. When I modulate my Transmitter, The pattern holds steady and does not dance all over the screen.  I dont know how I used scopes before without the Trigger. I am now selling off my Monitor scopes.  I wont use them again.

I got the AM5k and its working great with my GK500C around 300 watts of carrier. My scope has enough Gain to calibrate right on the money. Get the 2K if you have less power then the king does. I wanted to use one pickup for the King, The Big box and my T368 so I got the 5K model. I was worried it would not have enough output to the scope but I got lucky.

Also. The audio output jack and variable is a nice feature. I have been using it pumped through my audio system. Very clear and clean.

If you dont have time to build your own pickup, Just get this thing and be done with it. I am very pleased with it. It is VERY well made, Solid and has nice connectors and parts.  It also came with all the cables I needed.  First class for sure.

Now to get my USB O scope and 20 inch flat panel mounted so I will have a nice big scope on the wall in the shack!

I am not affiliated with him and dont know these guys. I just found it on the net and read up on the Triggering feature. Everyone seems happy so I purchased it.

c

I took an old $5 CB swr bridge, one of those things in a small steel clam box with a UHF jack on each end, meter, pot to adjust full scale forward, and slide switch for swr and turned it into something similar.  Some of them have a threaded recess on one end for screwing in a small field strength telescoping antenna.  Millions were made for Lafayette, Midland, Radio Shack, and a bunch of other CB manufacturers and you can get them for just a few bucks.  The inside has a rod between the jack centers and parallel rods for pickup.  Each are connected to diodes to rectify the RF and drive the meter.  One is for forward; the other reverse through the slide switch and the pot adjusts the current to drive the meter.  I drilled a hole and added a BNC jack and put the center of that on the meter pot wiper to get an adjustable level rectified signal to trigger on with the scope.  RF envelope tap is on the output of the 3-500s.  Diode tap is on exciter output.  Scope is an old Tek 453.  Very stable mod. envelope.  but I use the sb610 for trapezoid.   Of course this all works to the extent it does because I'm doing the exciter driving the leenyar thing.   When I run a transmitter I'll have to make some changes.

Yeah. I made my own out a an old Bud box and some connectors. This thing works so much better. I hate junk tossed togther. I like building stuff but if its not first class, I wont be happy.

I have it all integrated into the audio rack now. No RF anywhere its not supposed to be.  I was going to use this thing for every transmitter here. I might just get a couple more and Connect them on the back of each unit. This way, I can sample RF at the source of each rig in the room and leave the levels set. 

C

I Picked up 2 of them, one for the radio and one for my amp. Installed them and then I tuned up my amp with out looking at the scope. Then I looked at the scope and saw the pattern, It looked like crap. So with a few turns on Tune and Load, looking at the scope, My pattern was perfect. Ill never go with out these things hooked up again. Thanks Tyler I also got the 5K model.73 :)

After a night of using mine, I am very happy. I used it with the T368 last night and was able to see that the pattern was horrible. I retuned it and set the audio up again and now have a much cleaner signal.  Those monitor scopes I used in the past are near worthless.  I love the Trigger feature. I dont have to try to hold a steady tone to adjust the rig.

C

Thanks Carl, Ordered one for myself.
I got tired of the dancing displays too.

Fred

Every bit as good or better than the Clean RF design and a LOT cheaper.

http://home.comcast.net/~msed01/RFpickup.html (http://home.comcast.net/~msed01/RFpickup.html)

If you don't mind building something.

I think the magical part of the "CleanRF" is that it provides a trigger for the Oscope and you get a nice stable, non-dancing display.

fred

Most better quality scopes provide a choice of triggering the time base from low or high frequency signal content.  Trigger from the LF component to get a stable display of the modulation envelope. 

There may also be cases where you will need to use delayed triggering to examine part of a waveform.  In this case, one time base is used to hold off triggering for the other time base.  This same basic setup can be used to greatly "magnify" a portion of the waveform by using the first time base to hard trigger the second time base at the desired point on the waveform.

"A clean non-dancing display"  could you explain that a little more?  I just sample the RF out and feed that into an old TEK scope.  I can't say I love it.  Does this thing improve on that display

The design posted above is junk. I Tried it.  It does not work anywhere near as nice as the AM5k.  ITs lacking the entire trigger portion and its also for low power.

When you use the Trigger, You set the scope to EXT. So when your scope is triggered, the audio Frequencys dont dance around.  No matter if you put 500hz or 1000hz in, We see a nice display.  Maybe I can find time today to take some video with and without the Trigger so you can see it work.  Its clear some are not undestanding this.

I love mine!

C

For a clean display of the audio frequency component you have to trigger the scope time base on this component.  If your scope doesn't have the capability to trigger on the AF versus RF component then this gadget will provide that by generating a trigger source from its built in demodulator.  For most Tektronix, HP, and similar "lab grade" scopes the internal system will trigger "cleanly" :) from the trigger pickoff in the vertical amp. 

Of course if you have a line sampler you already like and a scope with a less sophisticated trigger system you can easily build a simple demodulator to provide an audio sample for triggering your scope.

I am running my station right now on 40.  Its cearly better using the AM5ks line to ext trigger. If I unplug it and try to use the internal on the scope, The Pattern is typical of what I was used too.  I have to hold a certain tone to get the picture to hold.  But with the demodulator set to ext the picture is spot on clear. Maybe my old tek is not happy trying to perform this funtion internal.

The Trapazoid is nice to have when tuning a Transmitter or SSB station. I found my Pro/Sb220 was out of tune this morning. Using the Trap feature, I was able to tune it linear. Then I switched back from Trap mode and set the audio right under 100. The guys actualy noticed on the air without me mentioning it. I bet my neighbors are much happier now.

I always used monitor scopes here on AM and SSB. But this is a new world for me. 

Neat toy.

C

Those things seem kind of expensive.  $129...over $200...for that you can do what I did and make a sampling rectified RF (audio) trigger source from an old swr bridge, buy a nice used Tek scope and/or SB610 monitor scope and have it all.   Actually, if I had to, I could get by with just the trapezoid.  If you have a dual trace scope, you can look at the mod. envelope with one trace and the rectified RF audio that you trigger on with the other trace.   It's just kind of fun to compare them.

Hey Rob. How about a challenge?  You up for it?  Build one that is better.. Then show it to us.

C

Clark,

If your boxes work for you that's great.  I'm not trying to one-up you.   I just thought folks who can't afford those things might want to know about another way that is less expensive.   Maybe it's not as good--I don't know--it works well enough for me. 

Awesome.. Now just design something that works as good as this or better and post it Rob!

C

Cool.  Can you post plans for this and the parts list. That would be cool. 

C

I dont want to open mine. Its working so damn nice I will leave it alone. I just see all these comments on how you can build one and save money but then nobody ever shows how to do that.  Its like saying. I can paint my own house and save $1000.  But then when it comes time, They hire a crew and the job is done in one day.   I dont see any plans on how to make a device like this. The Trigger output is really working great. I took some videos of AM and SSB this morning. The Trapazoid is really cool on SSB. 

C

The RF ammeter I posted is junk?  That method is used in thousands of lab grade devices for longer than I've been on the planet. I have built or used them from 5 watts to 25,000 watts.  Likely you didn't read my entire post. And I know what's inside the Clean RF box, there's no magic in a demodulated AC coupled output for trigger.  Sorry to have wasted your time.  Guess I'll throw away everything in my engineering library now that you've straightened me out. Thanks.

I am not sure what you are talking about on the RF ammeter thing.  Sorry.

Its easy to talk about how to make something like this. But its another thing to actualy sit down and make one with all these features.  Whats the shame in buying something if it works better then anything on the market?

I understand hams are cheap and they want to build stuff out of junk. I have made all kinds of things myself :)  But this thing has the base-band RF demodulator providing the EXTERNAL trigger and I have yet to see an easy way to do that nor do I have the time right now in life to try! 

I ran my unit at full power SSB today on 40. It was really neat seeing that envelope in sync. I was unplugging the trigger and going back to internal Time on the scope and wondering why I did not buy this thing 2 years ago when I first saw it! I guess I did not fully understand what I was missing.  I am sure someone will now come up with a parts layout that works like this one and offer an article and instructions. Maybe in QST!  They will probably Drill the rivets out and post pictures also.

Happy AMing!


C

I got something that works just as good and it costs nothing. It's called a good scope. I've never had any dancing patterns because I use a scope that has a decent trigger section. No external trigger is required. And it doesn't mean you need an expensive scope. Several ham fest $20-40 scopes have served as my mod monitor for the last 20 years.

I'm sure that box is nice. Have fun with it.

Right on Mark, Heck I bought a TEK 7904 with plug- ins for under $200 and it will trigger on a 1 GHz sine wave.
Why pay big bucks for an interface to a junk scope get a real scope and learn how to use it.

Yes I see the point. We all need to use a 1 Ghz scope on 80m AM! These usually cost more than a few hundred bucks the last I checked.

I have had several Tektronix scopes over the years, nothing high end, but scopes like the Tek 465, 2225, 547, etc. Of the lot the old large 547 did the best triggering on an AM envelope. I currently have a pair of 2225's used for AM. These things trigger just fine on a periodic waveform like a sine or square wave. With a modulated RF envelope the triggering is erratic, and sometimes infuriating. With my Central electronics 20A station I use the audio sample from the 20a to channel B, RF to channel A, while triggering on channel B. This works fairly well, but sometimes I have to fuss with the scope when changing the sweep time per division.

I took home from work a portable Tek with an LCD screen once. This was a digital sampling scope, about 100 mb/s I think. There was NO way this POS would trigger on an AM modulated envelope. I tried all the settings. That scope costs over $2K new too.

It is my opinion that an external scope trigger for AM modulation monitoring is the least hassle. Take it a step further and use some sort of threshold comparator to develop an external trigger that is more scope friendly, and you have a winner. I believe that this thread is about just that.

Maybe some of us can just accept that this product that Clark is using has something going for it, and for some applications that's just the ticket. Sure we can all cobble up something in a bud box as well. But how well will it work? Your mileage may vary.

Jim
WD5JKO

Jim,

Does your 2225 have a high frequency reject position for trigger coupling?  I am sure your 547 must since my Tektronix 556 (dual beam but same vintage as your 547) and the 7B series time bases I use with my 7000 series scopes all have this and it provides stable triggering on the audio component of the waveform.

I use a pair of 7854 digitizing scopes on the bench and I picked both of them up with their keyboards (needed for waveform analysis) and all plug-in slots filled for $125 each at a hamfest.  Scopes like this are excellent performers but obsolete from the industry point of view so they are cheap.  I have a 7623A  analog storage scope dedicated to a 7L13 spectrum analyzer and that pair was $300 but spectrum analyzers are still expensive

Wow steve.  Thats cool. I wish I could afford a scope like that.  I have an old Tech we paid $20 for.  PRetty neat..  I bet those big dollar scopes will come down in price and I can get one this year.


C

Guess you didn't read my post.    :D   I typed:


I also have a 100 MHz Tek that I got for $75. Take a look at the next hamfest. You may snag one.
  

a 1 GHz scope is great for looking at a class e rig waveforms
My point is a good scope is cheap so why spend a bundle on an interface that does the same thing as a real scope trigger circuit. TEK LCD scopes are great but you have to learn how to use it.

I've got several 100 MHz scopes and never paid more than a hundred bux for any of 'em.  My 7903 has the freq counter plug in and it triggers perfectly.   I also have a Gould portable scope (the size of a 2245 etc) that's got a built in freq counter and it works FB on AM signals.  A decent hamfest will cough one up almost every time.

The other issue with tunnel diodes is they are known for changing characteristics and a number of folks have written about searching for replacements for their vintage Tektronix scopes.  I have some old 500 series lab scopes and plug-ins that use tunnel diodes but so far they have been good to me.

Didn't Heathkit make a dip meter using a tunnel diode?

And it dont got no stinkin BNC conecters.........................


klc

Real boat anchor scopes have a separate power supply and the requisite scopemobile :) 

The type 555 dual beam with plug in time bases and vertical amps.  Both the scope and power supply have cooling fans and it will never get an energy star award.

http://amfone.net/Amforum/index.php?action=dlattach;topic=24445.0;attach=20152


I used to have one of those. It was one hell of a scope, HOWEVER....................

It took 4 men, 2 boys, 3 teams of horses and a tribe of indians to move it!! It would also do a nice job of keeping the shack warm in the winter!! The fellow I gave it to is still using it!

those are some beaut tube scopes--do you have to run them on 115 v. for the tube filaments?

I just scored a Tek R7704 for the bench and a small Sola 500 VA 120 v. conditioner.  I have no idea what I'm gg to do with it but the price was too good to pass, so I figured I'd experiment with power conditioning and see what it buys me.

While all scopes provide triggering selection control, it does no good to set the trigger up to source "internal" off the input you are feeding from a stand alone sampler.  In order to hold the wave form in a synchronized way, one MUST use a base-band RF reference rectified EXTERNAL trigger signal.  The Clean RF has provided this option, in addition to providing a separate audio source feed to their 1/4 TRS headphone jack with volume control.
 
When I move the trigger selection to internal off from their external based signal, the wave from DOES NOT stand still, it moves all over the place every time I change the pitch of my voice, the CleanRF Systems external trigger solves all that.  I can not believe I used a stand alone sampler for some time.  It is junk, you need to trigger the signal.  If you have any questions, go to their site, the documentation is off the chart. 

Your not understanding.  I tried over and over to explain to you.  Maybe you have to see this work in person before you get it.

C

Roger,

   Yes it does, and some other options. The trouble with triggering this way is that the results are inconsistent with most any setting using my voice as a trigger source. As a result I use X:Y mode mostly since with a Trapezoid pattern there is nothing critical about the setup.  

  Boy listening to some of the other posters here, we got some pretty high level scope users here on AM Fone. I bet some of these guys could analyze perfectly a single shot 20ns pulse with a Hickock OS8 oscilloscope.  ;D

http://www.oszimuseum.de/oszimuseum/equipment/manufacturer/hickok/os8bu_200.jpg

Jim
WD5JKO

http://www.tek.com/cgi-bin/rfbypass.cgi?link=http://www2.tek.com/cmswpt/tidownload.lotr?ct=TI&cs=pri&ci=2280&lc=EN

7704 is a nice scope a slower 7904.
I've seen the manual on line free. BTW I just downloaded the service manual for my 2240 for free.

Wow.  I feel like I need to take a class on the oscilloscope now.

Boy, these guys still are missing the point.  It is not whether the scope has a trigger, it is whether it provides the base-band signal to trigger the RF band input.  What is so hard to understand about that???   

Not trying to argue here.. I just think you are not understanding why its important to have the base band signal Trigger.

C

Like many of the others here I have several Tektronix scopes and the trigger circuit WILL trigger on either the RF "carrier" or the modulation component depending upon trigger setting and sweep speed.  That is a basic requirement for a good scope, that it can trigger on different components of a complex waveform.

If you are using a Heathkit SB-610 or similar recurrent sweep scope you are going to struggle to get a stable pattern.  But if any of my Tektronix scopes were unable to provide a stable display of a modulated carrier or a string of CW dots or dashes it would be time to troubleshoot the timebase and its triggering circuit.

Tektronix scopes were standard equipment in most AM, FM, and TV stations from the 50's onward.  The only thing used beyond the standard trigger circuit was a unit allowing switch selectable display of any line of an NTSC waveform; even this could be done using a dual timebase unit in "A delayed by B" mode but it was a lot easier to switch select with the dedicated trigger unit.  Tek later build specialized display monitors for TV use with this trigger/timebase built in.

Roger,

  I just got off 75m where I ran AM, SSB, and AM again. The first two were with my 20A. I use the 20A audio sample output to the second channel and the modulated RF in the other. The scope is a Tek 2225 (50 mhz). Everything worked perfect, as the triggering was stable, and repeatable.

  Then I switched to my Gonset G76 where I could only use one scope channel since I have no external audio here, so I had to trigger on that. The results were not very good. After the QSO I switched to a dummy load to examine the issue further. Playing with the trigger level, trigger coupling, LF reject, sometimes HF reject, and a few other knobs I could trigger the scope repeatedly with exact sustained Yeaaaaaaa Yeaaaaaa. Then say Hellllllooooo, Hellllloooo and I need to fiddle with the knobs again. For each sustained syllable, varying the sweep rate fine knob reveals sweep rates that will not trigger on, and others that will, and do so repeatedly.

   So my belief that a mid level scope like a 2225 is not so sophisticated in the trigger department, and possibly suffers some from age (leaky or diminished capacity electrolytic condensers). The operator (me) might suffer from some of the same ills.  ;D

   If the product Clark posted would enhance the capability of a modulation monitor scope like mine, then why would folks infer that the problem is simply a short between the headphones?

Jim
WD5JKO

I am not sure..  I honestly think it is because they have not used the Trigger setup like this.  I have an old Tek scope. Ancient model 422.  It works 100% with the outboard Trigger from the Clean RF device. I used scopes for years without the Trigger and I had no idea what I was missing. Now that I have it, I wont go back.

C 

Rodger is on point.  If you have a scope with a good trigger section (and you know how to use it), the baseband trigger input is not needed. This is not an arguable point. It's been done for years. It's not a misunderstanding of what anyone is saying or what the CleanRF box does. It's the FACT that the CleanRF box is not needed given the right circumstances.

I have a 2235 and I have no problem triggering on AM waveforms. It's a few years older than the 2225 but nearly identical, except the BW is 100 MHz vice 50 MHz. Just like my cheapie BK Precision 1541B (which also triggers on the AM envelope FB), the trigger section has LF coupling. I find with the proper setting of the timebase and if needed, the hold-off control, the LF coupling isn't even needed. But using it, does make things easier.

 I don't think anyone implied there was a "short between the headphones." If you inferred that, then it's on you. We can all learn from the experience of others. I don't see someone teaching me something as implying I'm stupid (even if I am stupid, as is often the case).  :D

That's it and that's all. No arguing and no one-ups-manship.

Jim,

It is very possible that your trigger circuit is not operating as intended.  The full calibration procedure for a scope is not even close to rocket science but it can be tedious and like everything else test gear requires periodic checks and calibration.  Calibrating test gear is actually the most important calibration since everything else you repair is dependent upon your test gear performance.  I can calibrate most analog Tektronix scopes in an hour to 90 minutes max.  Some of the early scopes, like the Type 555 pictured earlier, take longer since the vertical delay line is composed of L/C circuits instead of a simple coaxial line.  Adjusting these requires a fast rise square wave generator and a bit of patience to adjust the delay line to provide the required delay without changing the waveform.  Scope makers soon discovered a coaxial line could be used to provide the delay and that takes a couple of hours out of the typical calibration.  The delay is necessary to allow the time base to be triggered to start the horizontal sweep before the vertical signal is applied.  Otherwise you would not be able to see the actual triggering event.

To trigger on the audio component you want to set if for HF reject.  I have never used the model you own but it really should cleanly lock with little/no fiddling of controls and once the trigger settings are adjusted you should be able to switch sweep time per division without resetting this control (until you move outside the speed range where the trigger mode you selected doesn't make sense; i.e. setting a very fast time per division when what you actually want is the audio component).

Clark,

I have no issue with the box you are using.  If you have a scope that either has a less sophisticated trigger/time base or one that isn't working properly then it essentially provides a hard trigger for the time base based upon the audio component.  But for the scopes that are commonplace in many ham stations it isn't necessary.  

In general, if you are repairing your own gear owning and learning to use a good scope will pay you back many times over.  I have used the scopes several times to locate those annoying intermittent problems that plague both modern and vintage gear.  Some things can only be done properly with a scope and many measurements are much easier with a scope.  I like the Tektronix 7000 series because they are inexpensive (at hamfests) and very versatile with the available plug-ins.  I have several of the 7000 family but most used are my 7854 models which provide a conservative 400 Mhz. bandwidth with storage and waveform analysis built in.

Thanks Steve.  I will look for a better scope at the next swap and swindle. 

C

Thanks Frank; I'll look for the manual.  The 7704 will probably handle anything I get into. 

Da, my digital scope is a 2430. I think the memory hold up battery is shot.
It started coming up with faults a month ago. After some reading it appears the calibration constants are messed up. I need to replace the battery which will force a relaod of a default base line table so it will calibrate itself again.
My 7623 just keeps working. The old 7000 scopes were great. 4XX series had problems with transistor sockets. Best way to fix the problem is to solder the transistors into the socket. 5XX worked great and make nice room heaters.
My old 545 drew about 7 amps off the line. The new LCD scopes are cool once you learn how to use them.

Rob. How is the design stage comming along?

C

<<<4XX series had problems with transistor sockets. Best way to fix the problem is to solder the transistors into the socket.>>>

Thanks Frank, I have two of those.  I thought the transistor sockets were a nice feature  :D I hate to solder them; maybe I'll re-seat them if there's a problem.  

Clark, what are you talking about?

You must be asking about the SWR bridge mod.  Go back and read my earlier posts.  If you are asking for a schematic diagram the "design" is so simple it hardly needs any diagram.  Get a elcheapo SWR bridge, the kind that inserts in an unbalanced feedline with a meter and a "forward/reverse" switch.  They have a meter set pot.  The idea is that you transmit a carrier and adjust the pot so in forward position the meter reads full scale. You flip the switch to "reverse" and read the line SWR.

Well, the bridge has a couple cheap glass diodes that rectify the picked up RF to drive the meter movement.  They are connected to the wiper on the pot via the switch.  That's your rectified RF.  You need only drill a hole in the cabinet, insert a jack (BNC or RCA phono work best) and run a short jumper from the jack center to the pot wiper.  use some kind of coax jumper from that to your scope trigger.  That's the "design."

For pickup of the RF you probably have that taken care of.  I didn't even bother making a probe box; I simply used an available jack on a feedline coax switch.  The isolation is good enough so I get enough signal to see without blowing anything and I have it arranged to prevent accidentally transmitting into the scope, which would be a real bummer if it were to happen.  :o

My first scope was an old Tek 475 I got from work for fifty bucks.  I did not know it at the time but it was not in very good shape and this is what I tried to get a stable display.   I still use that scope to see received mod. envelopes via an IF tube tap on the 75A3.   It is tricky because I only have the signal to trigger on so I have to get it just right and Ioose it if the amplitude drops. 

Rob

Rob. You are being combative for some strange reason. You spoke of a better design that was cheap. I would like you to design something for us so we can all use it. If you cant do that. I understand.  Sorry.

C

Rob, think about it, how often does a transistor wear out in a well designed circuit? the 4XX series was just after the tube days. Another problem was many of the transistors had the leads cut too short. Early 4XX series were the biggest problem. If a transistor ever fails it isn't a big deal to desolder it.

Frank, good point.  right after tubes; short leads...


Clark,  I can't imagine how I seem combative but I assure you that could not be further from my intent and I sincerely apologize--I would like to be able to have a friendly QSO with you some day on the radio and consider you a friend like everyone else here.  Please go back and carefully re-read my earlier messages.  I never claimed to have anything I thought was better as a design--cheaper yes--in fact I think I even wrote that your product might be better.   In the long run we're just talking about a mod envelope on a scope.   It's really not a big deal.  Please enjoy your boxes and God bless you.

Rob

Back in the first page you talked about building something cheaper that would work. I asked you to show us.   Sorry if I came off rude or anything.

C

Clark, Rob described his box in the first reply to your initial post.  Not sure why you're getting spun up about it and demanding that Rob design something for you.

This is a hobby, and there's room for all manner of ways to do things.  Don't take someone else's method as a challenge to your way.  If you like it and you're having fun with it, that's what it's all about  ;D

I am not getting spun up.  He told me he could make something better for next to nothing. So did HRO. But then they never posted how.  I wanted to learn how...

The trouble with suggestions here is that it will blow up headphones.  Using the diode for the audio wont work as its not filtered.  Try that with a high power transmitter and see it smoke your nice headphones.  Raw DC.  Been there done that. It would be nice if someone puts out claims, they actualy show us how. Cause Rob told me that he could make this for $20. I just want to see that. I need about 5 of them. One for each transmitter!

Cya and sorry if I came off the wrong way. Sometimes its hard on text to judge how someone is acting.

Clark   

The problem with the 4XX series transistor sockets was the  contact plating wore off from the motion of going in to wiggle each one trying to bring it back up. I remember the cal lab guys at one job having fun with these scopes.
Outside of the transistor socket problem they all were very good and a lot easier to lug around than the 5XX tanks. 

HRO.. I tested this with a modern scope and the old Tek 422.  The modern scope without the trigger input is not nearly as stable as using the trigger.  The reason I believe is that you are sending base band audio to the scope directly as the source.  Also. The outputs for audio are DC blocked and filtered. 

Cya

Clark

Oh.. Sorry for the confusion.  Above in the thread it was suggested that if you had a modern scope, You dould not need this.. Only the RF pickup. I guess I got confused. I had my friend bring over a 350mhz scope and we could not produce the lock on the envelope like we can with the Clean RF Trigger.

Clark

Did the scope have the "HF Reject" feature in the trigger circuit?  Most Tek scopes and even that POS Gould I have has this.

JN,

The only Tek scope I have without HF reject is a type 514AD that belonged to my father.  It has a specified bandwidth of only 10 Mhz. and a somewhat touchy and awkward trigger/timebase system.  However, it does provide direct access to the deflection plates for high bandwidth applications.   My father used this to teach me how to calibrate scopes when I was 14 and I cannot remember how many iterations I made through the vertical delay line procedure until I finally got it right.