How does the DG212CJ function in the post secondary transformer set up? I've tested and found the 5V fed from the voltage regulator and also found +/-15V on the DG212CJ. I found 15V on pin 8 of the 4558DD Dual Op amps in the schematic above. Since I haven't looked under the board is it safe to say that pin 8 of one of the op amps is feeding the voltage to the DG212CJ?
I'm having a little trouble reading the schematic as I don't see where they would take off the 15 volts to feed the pre-amps section. Where does that usually happen? Thanks, Hawk (the new guy!)
Many times on schematics there are voltage supplies given but no explanation to exactly what other circuit components it is derived. In this case, trace the board from the chip (pins 13 & 4) to confirm that it's voltages are fed off the opamp power supply. I guess we just know that the opamp power supply is the same source and the engineers simplify the schematic that way. So, DG212 is connected to pins 4 & 8 of the opamp power supply.
Thanks DrGonz78! Appreciate the response. I follow what you are saying.
That's a really poorly drawn schematic. I wouldn't be surprised to see "blue wires" that connect the DG212 supply pins to +/-15V.
Well, that's a usual problem .... but in this particular case, you are being unfair with poor old Marshall (RIP)
In page 2 of the schematic, it's clearly shown that +/- 15V feeds pins 8 and 4 of all dual Op Amps (RC4558 and NE5532) and pins 13 and 4 of DG212.
It is also clearly shown that said DG212 gets +5V on pin 12 and that pin 5 is grounded.
So stop bashing poor old Jim :trouble
:lmao:
Thanks for the last comment regarding voltages fed from. But, silly question I'm sure, where exactly is the -15/+15 volts picked off from? On page 2 of schem. where it shows V+, V-, I measure +34 volts to ground, and -34 volts to ground, both from R10 and R11. Thanks.
Quote from: Hawk on February 06, 2015, 08:43:51 AM
Thanks for the last comment regarding voltages fed from. But, silly question I'm sure, where exactly is the -15/+15 volts picked off from? On page 2 of schem. where it shows V+, V-, I measure +34 volts to ground, and -34 volts to ground, both from R10 and R11. Thanks.
That's the "main"supply, for the power amp (which runs on +/-34V) but there's also others :o
Depending on how you count them, you have 3 , 4 , or 5 supplies there, in 3 blocks.
The top one is simple, main windings W5-6-7 feed BR1 and charge C33-34 to +/-034V ... what you measured.
The middle and bottom ones are fed from W8-7-10 , rectified with D10-11-12-13 and, curious enough, because it's a voltage doubler circuit, they get roughly +/-10V and +/- 20V :o
The middle +/-20V get regulated down to +/-15V with regulators Reg1-2 and thereb you have your +/-15V .
In the lower one, they again rectify with D4-5-6-7 , get roughly 10V (might be as much as 12V raw) and straight feed the fan, which probably is a PC 12V type (cheap and plentiful) and those 10/12V get regulatyed to +5V with Reg3 , for the +5V pin on DG212 .
Thanks JM! Off to work now but will study up on your info later today. Thanks for taking the time. (This is a fantastic forum!) :tu:
D11 is charred and reading O ohms both ways. Any comments on how that would effect the circuit/amp? Hoping to replace it tonight or Monday
Quote from: J M Fahey on February 06, 2015, 01:42:53 AM
Well, that's a usual problem .... but in this particular case, you are being unfair with poor old Marshall (RIP)
In page 2 of the schematic, it's clearly shown that +/- 15V feeds pins 8 and 4 of all dual Op Amps (RC4558 and NE5532) and pins 13 and 4 of DG212.
It is also clearly shown that said DG212 gets +5V on pin 12 and that pin 5 is grounded.
So stop bashing poor old Jim :trouble
:lmao:
The only reason that schematic was drawn is to generate a netlist so that a circuit board could be layed out. The person who does the layout probably never even looked at the schematic. The netlist utility will tell the circuit board program to connect everything that is defined as "+15V", but not to the output of the 7815 because it's not defined as going to the net "+15V". See how there is "+5v" near the output of the 7805? There is also a "+5V" in the upper left corner near R79. Those two points would get connected.
Poor old Jim probably wouldn't even recognize what his company has become. All over that schematic there is text on top of wires, components and other text. This tells me that there is no pride in workmanship. Nobody even put their name on the schematic. Perhaps they don't even speak English.
Amen to that! For me that pretty much describes the state of modern Marshall schematics. Occasionally someone online will make up a drawing showing which connectors go to what. Otherwise they are a nightmare. I often wonder if the actual factory techs have secret maps of the connector routing. If they still have such a thing as factory techs....
Hawk: D11 is part of the supply feeding the 7815 regulator. As you mentioned you are getting +15V to the op amps, it is not causing much problem at idle. But perhaps when passing signal the +15V would be dropping and making trouble.
Quote from: LoudthudAll over that schematic there is text on top of wires, components and other text. This tells me that there is no pride in workmanship. Nobody even put their name on the schematic.
Indeed - "You never find just one roach in a kitchen". These observations tell us a lot about the culture of the workplace and how management operates - sloppy is good enough.
Quote from: g1I often wonder if the actual factory techs have secret maps of the connector routing.
Having done some production line servicing I'd say that is highly likely, at least to bring newbies up to speed. {but after that fiasco of the wrong value resistors in the output stage you really have to wonder...}
QuoteThe only reason that schematic was drawn is to generate a netlist so that a circuit board could be layed out. The person who does the layout probably never even looked at the schematic. The netlist utility will tell the circuit board program to connect everything that is defined as "+15V", but not to the output of the 7815 because it's not defined as going to the net "+15V". See how there is "+5v" near the output of the 7805? There is also a "+5V" in the upper left corner near R79. Those two points would get connected.
Poor old Jim probably wouldn't even recognize what his company has become. All over that schematic there is text on top of wires, components and other text. This tells me that there is no pride in workmanship. Nobody even put their name on the schematic. Perhaps they don't even speak English.
You are right, of course.
A BIG complaint I have about many "modern schematics" is that they are not so, but simply a printout of the .SCH file generated by the PCB layout software.
And parts do not interconnect ... because software would try to draw tracks between different PCBs which of course that's nonsense.
Software accurately draws tracks ending in connectors ... because that's all there is in any particular PCB.
Connector/wire harnesses are something else, of course they are drawn somewhere but they are sent to some OEM wire harness supplier.
At least Marshall in general shows connectors (not always); the worst offender I know is SWR.
Just try to make sense out of
this:
not a f*****g pot , jack or switch is drawn!!!! (because they are mounted in small sub PCBs :trouble )
In fact the drawing itself is clearly labelled xxxxxx.sch file.
Although Marshall has some schematics where the TUBES are not shown, but plate and cathode connected parts are ... for the same reason, tube sockets are chassis mounted :duh
As of who signs the schematics, I'd often see small blank rectangles instead of letters.
Until my Son, who speaks fluent Japanese, installed Windows Asian Fonts Pack in my PC ... and all those little rectangles started showing up as Kanji characters, go figure.
Thanks for these posts. I just figured I was missing something with regards to schematics. Good to know I'm not alone and I'm not completely out to lunch! Is it worth contacting Marshall/SWR to ask them why they don't supply proper schematics? Or is it a case of not wanting techs to fix their amps? Would they rather the customer chuck the amp in the garbage and buy another one? Seems that way to me...any thoughts?
Quote from: Hawk on February 06, 2015, 08:24:10 PM
Is it worth contacting Marshall/SWR to ask them why they don't supply proper schematics?
Heavyweight techs I know have complained to Factory representatives, both Marshall and other brands, face to face (or over a couple beers) at NAMM ... they answer
"you are the only one who complains, everybody else is happy" which of course is a bucket of lies .... but then,what to do?
They don't care.
Most Techs curse a little, shrug their shoulders and continue repairing.
Mind you, if you have the actual amp spread eagled on your bench, you actually see where the connectors go, so it's not
that bad.
But it sure complicates "distributed repairing over the Internet" such as we are doing now.
QuoteOr is it a case of not wanting techs to fix their amps? Would they rather the customer chuck the amp in the garbage and buy another one? Seems that way to me...any thoughts?
Not that much; I think they are just lazy.
I guess the guy they hired to run the "Schematic design and improvement" department is working extra time:
(http://michelletessendorf.com/wp-content/uploads/2012/06/Lazy-guy.jpg)
For the novice it must be infuriating. Some drawings might have a takeoff point for say reverb, and there would be a short line off the signal path with REVIN next to it or something. On the Marshall drawings there might be a little SEND next to the signal path between two stages, and we must infer what is going on.
I don't like it either, I like old school drawings as much as anyone. But some things are to be universally understood, like the distribution of +/-15v, and it is common these days to put all the IC power feeds on one page, just like tube amps used t draw all the heaters in a row by the 6v winding.
But once you have seen the screwy Marshall convention used here, it will be familiar the next time we see a Marshall.
Thanks JM and Enzo :tu:!
Advice needed: I'm about to remove the circuit board from the amp but it has plastic poles/standoffs. I've tried a small amount of prying but the board starts to bend. I don't want to crack the circuit board so can anyone suggest a good way to remove the board from these plastic standoffs? Also, would you unplug all the connectors in advance? I have to replace a diode, need to discharge caps, and I want to trace out the circuit board for learning purposes. Thanks!
Post standoff pictures, there are different types.
Maybe they are PC motherboard type, but will wait for your pictures, there are many types available:
(http://image.ec21.com/image/jane8/oimg_GC05402888_CA05413251/4mm_Diameter_PSC_Spacer_Support_Plastic_PCB_Standoff.jpg)
(http://www.pinbits.com/images/DSCN2498.JPG)
(http://www.hammondmfg.com/PCB2_B.jpg)
(http://ecx.images-amazon.com/images/I/11Q23XG8E8L.jpg)
Also on some marshall models you release the standoff from the outside of the chassis. Sometimes by screw, sometimes by 2-piece black plastic push-pin.
Here are the pics inside and out of chassis. What is the best way to remove? Thanks!
Pics are a bit blurry and can't really see the detail all that great. It seems there is one small part that hooks in and holds that standoff in place to the circuit board. Take a small straight blade screw driver and push (nicely) that piece in as you pull (nicely) up the board to remove. Sometimes they spin around and stuff. Also could use needle nose pliers, but they can tend to rip up the plastic piece. If you do it right each time it gets easier to remove however sometimes you end up wearing the piece out if you do it to often.
Thanks Dr. Gonz I'll give it a try!
Easy.
It has an "arrowhead" going through a hole in your PCB .
As`a good arrowhead (or a fishing hook yip), easy to go in, hard to go out.
Although your picture is somewhat fuzzy, there are 2 basic ways for that arrowhead to be stuck (on purpose) holdingbthePCB
1) it's a rhomboid shape, with the tip in a narrow angle and the base a much wider one.
When you push it into the hole it narrows, goes through the tiny hole and then expands to original size.
Going backwards is much harder.
You must squeeze it narrow with long nose pliers while lifting the PCB.
2) it may also have a third center leg which is somewhat bent outside the hole,
When inserting it bends inwards (it's very elastic and tough Nylon) , then snaps outwards again holding the PCB.
You pull the PCB while simultaneously pushing the center pin in with a small screwdriver.
3) a combination of 1) and 2) .
In a nutshell, imagine it's a flrexible arrow tip which squeezed thin to get into that hole and then expanded; you must repeat that backwards.
Quote from: J M FaheyYou must squeeze it narrow with long nose pliers while lifting the PCB.
This is easiest if the pliers are perpendicular to the axis of the standoff, i.e. coming from the point-of-view of <Standoff1.jpg>. I have several pairs of suture clamps/hemostats which are almost ideal for this in "busy" board environments.
Tip: anyone who does this a lot (e.g. working on computer motherboards) can also make up a specific tool using a small length of metal tubing (with the ends deburred/rounded), pushed down over the arrow. Old (simple) biro tubes will also work 'tho they tend to break fairly easily.
Thanks Gents! Easy is right, as it turns out. Used a pair of needle nose pliers, squeezed arrowhead and pushed up simultaneously and it slid through. It was easy, but glad I asked, better than cracking a pcb! :cheesy:
Might as well ask. How does one remove the connectors from the board without causing damage? The top section of each with all the wires: Con 1, Con 2, Con 3, Con 4. thanks! (see attachment)
Newb question: I measured 1.3v DC on pin 8 (V+), and -15.36 DC on pin 4 of NJM4558. I checked others in the circuit as well, same readings. Now, shouldn't V- and V+ have the same voltages? I thought they would both be -15.36. An equivalent circuit usually shows the same voltage on the rails, neg. and pos. Also this is a dual op amp, so....hmm, what am I missing? ??? Thanks.
The connectors are just push-in. Try not to pull by the wires. At each end there are little lip edges that you may be able to get your fingernails under. Or a flat head screwdriver to pry each end up a little till it comes loose.
In you first post you had your +15V. Now it's gone. Either something has gone bad or there is a connection issue. Check at the output pin of the 7815 regulator, there should be +15V there. If it is not, either the regulator is bad or something is loading down the +15V line, like a shorted IC. Or the regulator is not receiving it's input voltage (probably around +20V or more).
If there is +15V at the regulator output, then it is probably a connector issue or a bad solder joint or cracked trace somewhere. In this case, check all the IC's for +15V, if some have it and some don't, it may help localize the problem.
Update: found 1.3 V output on Reg. 1, -15.36 V Output on Reg. 2....D11 had been burned out so I replaced it and it is reading normal. The amp was working but maybe when I pulled out the circuit board (I was careful) I loosened a solder joint? Thanks.
Checked all the IC's and yes -15V on pin 4 and 1.3 v on pin 8, the analog switch has -15v on pin 4 and 1.3 on pin 13.
Looks like R108, the 2.2 K 1W resistor is charred, showing .34 VAC to ground on the circuit side, whereas the other one, R109, shows 11.34 VAC to ground. I measured R108 in circuit and it showed a read of 44K...will have to wait until tuesday to pick up resistor...hopefully this explains why I'm getting such a low voltate output at Reg 1 and therefore all the ICS.
Yahoo! Amp works again! After replacing resistor and diode I found proper voltage on op amps, voltage regs 1 and 2, and the analog switch.
Thanks for everyone's help so far.... :tu:
Next issue: amp still works fine, can play guitar through but when I power on the amp makes this nasty loud honking squealing sound for a good second, almost two then goes quiet and runs fine. When I turn off the amp it makes a very loud clicking sound.
I'm wondering if this problem has to do with the Metallized Polypropolene 100nK 275 Volts cap on the line side...
No. :)
This is with nothing plugged into the input? Do volumes have any effect?
Plug something into FX return jack, still same problem on turn on?
Quote from: Hawk on February 18, 2015, 10:38:08 AM
I'm wondering if this problem has to do with the Metallized Polypropolene 100nK 275 Volts cap on the line side...
NO , DEFINITELY NOT, line transient filter caps can have
NO effect on
anything soundwise.
Clear enough?
Clear enough. So that nasty sound occurs sometimes but not always. Plugged a jack into the FX Send but couldn't hear the nasty sound when I turned the amp back on. I have the bare pot shafts exposed so I turn them without the knobs. On the Overdrive Channel when I touch the Volume shaft I get a local AM radio station coming through loud and clear! Wondering if this has anything to do with it... Just turned it on now and that nasty sound came back--noticed that the gain was maybe half way, turned it down and re-tried turning the amp on a few more times but no problem...problem is not consistant...I've tried different volume settings and couldn't get the nasty sound to reproduce.... :-\
When I plug my guitar in and touch the volume pot the radio issue is non-existant.
So I should be embarassed here! I believe my problem was a huge grounding issue!! When I put the board back in I didn't put on my nuts/washers and tighten them because I intended to take out the board and study some more components etc...so now radio issue gone, amp sounds great, no nasty noise at start up :-[ :-[
Don't feel too bad, modern ground schemes can be fairly complicated and often require complete re-assembly to run properly.
So it's all done & ready for use now? ;)
It is thanks! It sounds like it should and no crazy radio signals and horrible sounding start-up noise. It's my mule so I'm sure I'll muck something else up but that's how I've been learning. I was hoping that I could somehow have the board turned upside down so I could read voltages at certain points in the circuit board that I can't access from the component side. But obviously that would screw up the grounding scheme and would be asking for trouble. Guess it's a matter of trying to pinpoint the issue, then turn over the board (without power and of course draining caps first) and measure the components to try and find the fault. I suppose you could try and measure the PT secondary voltages by somehow scooping your test leads under the board but that sounds dicey :)
Second Question: Re: the DSP board on this amp. It's about 2X2" and has three chips on it and SMD components. My guess is that this is for the Digital FX processing. I can't see how this could be repaired as everything is really, really small. Would it be a case of chucking out the old one and ordering one from Marshall? It works, just wondering what others have to say about that and how they've dealt with it. Thanks!
Last question for the night :) At the guitar input there is a line that goes up and all around the page and ends up at Pain R. The line also goes to the Headphone Out and ends in a circle and then on the other side of the Headphone Out the line goes to the circle on Pain L and then Pain Left goes to Pain R. Then on the far side of the page this is either fed to Con 2 or vica versa. I understand the idea of PreAmp and Power Amp and older schematics make it much clearer. When I look at this it seems backwards to me. Looks like the master volumes are feeding pin 1 and 7 of the outputs of the opamps??? What does Connector One Feed??? Thanks again! ???
Sorry, I was referring to the schematic.
Quote from: HawkSecond Question: Re: the DSP board
Well, that depends. The more "commercial" you are, the more likely you will simply change the module as a part, but if you're curious/crazy/irritated by the throw-away society/equipped to handle SMD you might give it a slash, however unless it is something pretty obvious then it is likely to concern some silicon blob that is custom/unobtainium and be a waste of time and energy.
Quote from: HawkLast question for the night :) At the guitar input there is a line that goes up and all around the page ...
Well two actually.
The line appears to be a fancy framing line to delineate the preamp board. It is not a conductor.
Quote from: HawkLooks like the master volumes are feeding pin 1 and 7 of the outputs of the opamps??? What does Connector One Feed???
In the lower part of the preamp circuit the signal flow is right-to-left. It comes out of IC5A and B, through C39 and C44, and onto the top of VR13A and B, picked off by the sliding taps, and out to the main amps at PAIN_L and _R. Again, "PAIN" stands for "Power Amplifier INput" (implicitly the preamp output).
By convention signal flow is from left-to-right and power supply right-to-left, but not everyone observes conventions.
The inputs of an op-amp are on the vertical stroke, and the output from the point;
(http://www.learningaboutelectronics.com/images/opamp2.jpg)
We appear to have two CN1's (apparently a drafting error). One goes to CN2 on the preamp marked "TO REAR JACK SOCKET BOARD", and the other is one of the two that go to the power amp boards and mate with CON3 and CON4. (note that these connectors are drawn differently to show their gender).
Great, that really opens things up for my understanding! I see what you are talking about.
Still confused about power amp schem. Shows both having the speaker outputs at W12,13,14,15. On Con 3 we have W13 attached to Pin 9 and W12 attached to Pin 1 (similar for Con 4) On the last page of the schematic, pin 9 from Con 3 appears to go to pin 14 of the TDA7293 which is the ouput but Pin 1 goes to the inverting input of the TDA7293. In my mind these speaker outs should come off pin 7 and 8 as they are the neg, pos signal. Is this an AB amplifiers? Shouldn't we have two opposite signals at the same time? Guess I'm showing my ignorance here. How exactly does the signal go to and come out of the TDA7293? Thanks!
Quote from: Hawk on February 19, 2015, 09:20:55 AM
Shows both having the speaker outputs at W12,13,14,15.
...In my mind these speaker outs should come off pin 7 and 8 as they are the neg, pos signal.
No on both counts. We do not know where any W connections are going except where shown. W13&15 are shown going to outputs, the others not. Suggest ignoring them.
The output IC shown on page 3 is the power amp. The other circuit with W12 thru W14 is not.
Pins 7&8 are +/- supplies, not signal.
The output IC data sheet may be helpful.
Great stuff thanks. When you pointed out W13 and 15 as outputs the penny dropped. :tu:
The only thing that doesn't makes sense is when you say that 7 and 8 are +/- supplies. According to the TDA7293 Data Sheet pin 13 and 15 are the supplies and 7 and 8 are +/- signal which, on the schematic on page 3, go from 9 on Con1 to pin 14(out) of the TDA7293. To me that would make more sense to have, but I may be missing something. Thanks again!
Dunno what datasheet you are looking at but the one I have from;
http://www.digchip.com/datasheets/parts/datasheet/456/TDA7293-pdf.php (http://www.digchip.com/datasheets/parts/datasheet/456/TDA7293-pdf.php)
...shows pins 2 and 3 as the inverting and non-inverting inputs and pins 7 and 8 as the supplies for the "signal" or front end of the power amp, and pins 13 and 15 as the supply pins for the power end of the amp.
Thanks Roly. I have the same data sheet and what you say makes total sense. I think what I'm finding confusing is how the TDA relates back to CON1 and all its 15 pins. How is it that pin 10 of the TDA goes to the +power rail (12,14,15 of Con 1)? When I look at the TDA block diagram pin 10 is considered to be part of the "mute" and I find it hard to determine if that should be part of the -rail or + rail. Thanks.
Sorry I wasn't more clear about pins 7&8, using the word "signal" on the data sheet was a bad choice for them, as Roly mentioned, pins 2 & 3 are the inputs.
The chip has both standby and mute options. In the Marshall they utilize the standby (there is a delay circuit which acts to mute the chip during power up at sector A4 of schem.pg2). Because they use the standby, they tie the chip mute to the +supply so chip mute is never activated.
No problem thanks for these details g1. But where exactly is sector A4? I'm on page 2 of the schematic and can't see it...thanks.
On the borders of the page are numbers (top and bottom) and letters (sides). It's just a way of describing areas of the schematic. Sort of like latitude and longitude of a map. So find A on the side and follow across to 4 on the bottom and you will have the general area.
Never noticed those numbers and letters before but I found the are you are talking about. Great!
Anyone suggest some good ways to put test leads on hard to access components? My multimeter leads often get wedged in between other components and I can't get the metal testing tip down against the component lead. Sometimes I've attached a solid core wire and that has worked. Can you purchase a test lead with a long shaft? I'm thinking of my SSW220 and it's output transistors. I want to check voltages on it's pins but can't get me test leads to reach as they're just isn't room.
Spring loaded "hook" test leads
(http://www.lapsun.com/lapsun/5-31/LS-HM788F-1.jpg)
Nice, thanks.
I find these small single hook clips very irritating because they don't get a good grip on the lead under test and keep slipping off.
These double (and sometimes triple) "gripper" probes are far superior;
(http://parrot-invent.com/wp-content/uploads/2013/10/TwoHookCorp.jpg)
Much longer, flexible, and a much more secure grip.
Thanks for that! Where did you buy them?
Where I would buy them;
http://www.altronics.com.au/p/p0409-parrot-style-test-hook-probes/ (http://www.altronics.com.au/p/p0409-parrot-style-test-hook-probes/)
It would seem that "parrot" is a bit of a keyword for these (and if you have ever been bitten by a parrot you will understand why).
I have both types kicking around because, like all tools, each has its strengths and weaknesses.
Both those test leads definitely have their strengths and weaknesses. I have had numerous sets of the hook type ones and they always fell apart on me after months of use. I like how they could fit in tight spaces but they were sometimes not long enough. Then I got the longer double gripper probes and they were way better. I have retired those too as they now measure about 4-7ohms of resistance for some reason. At first I thought it was my extender leads that connect the DMM to the probes, but those were fine. I then measured across each gripper probe and both of them have the exact same resistance problem. Perhaps some quality control problem in China while making those probes? Oh well now I have picked up a nice pair of Fluke AC280 Sure Grip probes and I they are way more durable/reliable. However, I am still looking for some smaller probes that won't fall apart or become a resistor.
http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0CAcQjRw&url=http%3A%2F%2Fwww.amazon.com%2FFluke-AC280-SureGrip-Hook-Clips%2Fdp%2FB001WADEAK&ei=btLpVKD6MYGdgwSav4LoBw&bvm=bv.86475890,d.eXY&psig=AFQjCNH4uOHfdVEE1sYsfuN6m_lSo_PiVQ&ust=1424696281247259
Thanks those look pretty good. I'm using a basic Canadian Tire dmm so not sure if/how my probes would fit with the ones that you're suggesting. Are they universal? Do your basic probes fit inside these and they act as extensions? I should probably have a better meter, but it's what I have at the moment.
These leads look great in terms of getting into tight places....of course, it'a s fluke and maybe it's time I upgraded my meter....
http://www.amazon.com/Fluke-TP88-Rigid-Probe-Length/dp/B000VRFL10/ref=pd_sim_hi_5/189-2491408-6635005?ie=UTF8&refRID=1GR9TWDSY3W4DC603DRR
This isn't really a technical question so it's a bit out of my sphere, but I will note that the probes you linked to are plain pin probes, not grippers, and they are only rated to 60 volts which I consider to be quite inadequate. I also think that they are over priced for what they are.
You need to shop around electronics specific stores and suppliers in your region/country.
Roly I think that is what I will do. I also read an article about a guy who used alligator clips and sewing needles and shrink wrapped them. Thanks for taking the time!