Road Lead 220

[Euthymia]

Needing schematic(s) for a Road Lead 220.

Any help?

[Albert Kreuzer]

Too big to post it here (1.76MB .zip)
PM me your email address.

office - at - albertkreuzer.com


Cheers,
Albert

[Enzo]

Actually ALbert, for future reference, we can upload 1.95MB in pdf, and 3MB in zip.

[Albert Kreuzer]

Thanks Enzo.

OK then, here it is.
(I thought 1MB was the limit, but obviously this is for .bmp only).

Cheers,
Albert

[Enzo]

I think the upload limits got larger a while back at some forum software upgrade or other.

[hewo]

Road 100Watt Guitar Amp (Model_5010?)

Thanks Enzo.

OK then, here it is.
(I thought 1MB was the limit, but obviously this is for .bmp only).

Cheers,
Albert

1. Hi everyone.
2. I have the original guitar amp and it is worth making a comeback but i should first thoroughly check it.
3. Mine has a short reverb tank, and huge finned heatsink for two TO-3 sized output power transistors.
4. The combo 2x12 black tolex and speaker machined mounting rings frontside grille are okay.
5. I recall changing intermediate drivers and output transistors long long ago using NTE substitutes.
6. then it did not sound the same.
7. then i installed an independent toroid (digikey) plus minus 12v transformer to power the preamp using plus minus voltage regulators. the amp became very quiet without noise.
8. i recall the preamp pcb traces lifting excessive soldering iron heat, so i had to epoxy them back down and be very carefull with heat.
9. i saved all of the original road factory parts while blindly installing brand new digikey parts.
10. i could not recover that sweet sound. i don't know whether the poweramp idle is wrong or whether the pt is underdrawn shifting preamp power load off of it. i furthered chaos by replacing the two dc rail electrolytics with computer grade capacitors, i believe 10,000uf each rail. bass indeed beautiful this way, clean headroom too.
11. but i don't know if the drivers and power transistors are idling enough with the higher rails dc.
12. should i send pics?
13. your responses are welcome.

[Jazz P Bass]

The idle, static (ie: no signal, no load) voltages are marked on the schematic.
Good place to start.

[J M Fahey]

Very well made amps, and if parts substitutions are right (not so sure about NTE) sound should be the same as new.

That said, comparing actual sound with old memories is not always trusty.

Didn't you change speakers?

In a nutshell, unless you have a specific problem , such as hum/buzz/sound cutoff/oscillation/crossover distortion/non working control or channel/etc. , just "does not sound as before" is a very elusive goal.

[hewo]

road 5010 lead

Very well made amps, and if parts substitutions are right (not so sure about NTE) sound should be the same as new.

That said, comparing actual sound with old memories is not always trusty.

Didn't you change speakers?

In a nutshell, unless you have a specific problem , such as hum/buzz/sound cutoff/oscillation/crossover distortion/non working control or channel/etc. , just "does not sound as before" is a very elusive goal.

Thanks, mcm electronics catalog order, pair 12" electrovoice, 1993, model ev12L, L signifies long throw? Low frequency?
Gotta take a look at that particular idling quiescent current spec on schematic. Rail ps caps must be slowly variac'd upwards upwards? Can u just trust the telltale failure rupture indicator nipple thingy? Says mallory usa, blue cannistors. Then additionally there's electrolytics preamp and bias poweramp, some upgraded tants others digikey'd same 1993 era. When I bought it brand new, as a naiive college student, the slick city salesman selected it based on my financial lowlyness. But it sounded very appealing irregardless of class ab topology output. Let me get some pics of the preamp solder landings lifted repaired traces, recall pretty severe.

[hewo]

upload here pics road lead 5010, nope, denied 3Mb blockage, what do?
site: ftp://cchftp1.honolulu.gov
account: cchftpuser
password: cchftpuser
file: road.zip
size: 29.5Mb

[hewo]

turquoise ooze negative poweramp rail cap terminal junction

The idle, static (ie: no signal, no load) voltages are marked on the schematic.
Good place to start.

1. Anomally, need help
2. Negative terminal screw and connected leads contaminated with aquamarine colored ooze, dunno why
3. Witnessesd this in household power terminations too, is this patina?
4. Frightened it may be electrolyte yet telltale rupture nipple of cap perfect status
5. Could it be adverse chemical leaching out from the terminating wiring's insulatory materials?
6. Visual inspection of the wiring termination anchor reveals ooze crawling out from wire's insulatory, quite confusing
7. Cap out of circuit tests ok
8. Please advise. Variac restore on hold until this anomally cleared.

[g1]

Yes, I think it is patina.
It's presence indicates you should closely inspect all grounding connections to the chassis, such as pot and jacks nuts or star washers.
There may be severe oxidization at ground points and other points like the screw terminal of the cap.

[hewo]

SolidstateGuitarAmpResidualCurrentInWiringCausesEjectedP atinaViscousLiquid

Yes, I think it is patina.
It's presence indicates you should closely inspect all grounding connections to the chassis, such as pot and jacks nuts or star washers.
There may be severe oxidization at ground points and other points like the screw terminal of the cap.

Tube guitar amps do not exhibit patina, why?
It has to do with residual capacitor energy stranded over long time periods.
It has to do with old technology copper wiring, non oxygen free copper, and leaching of the pvc or equiv wire insulation (not mil spec teflon silvered wire).

I isolated the patina casualties and realized the copper is zero ohms conduction still. So I will not swap out using mil spec teflon silvered wiring.

I will research what chemicals are economically avail without side effects, just as we do for our automotive battery terminals exhibiting electrically driven accelerated "oxidation" using the atmospheric watervapor - this is corrosion, right?

amp sounds great, extremely high fidelity telecaster clear as whistle, but i want to reduce poweramp rails from 57dc to 47dc as schematic assigns. how do? utilize rail ballast resistors to drain off rail caps? drained rail caps averts patina during storage? two birds with one stone? recall preamp power independent now via digikey toroid pt, so orig road pt is relieved causing 57dc rails, more so because of capacitor increase from 6000uf to 10,000uf each poweramp rail.

your responses are welcome.
regards,
curtis

[J M Fahey]

Oh PLEASE stop overthinking

Starting from the beginning, your amp is working VERY well.

Shouldn't that be a clue?

Won't continue answering until your 29M of pictures or whatever end downloading, so bear with me.

Ok, I'm back.
1) very large but unsharp pictures are not much use, I halved size of yours, sharpened them and ... surprise ... lowered average >3MB *each* to average 200k each
2)

pair 12" electrovoice, 1993, model ev12L, L signifies long throw? Low frequency?

EV "L" use aluminum voice coils, KILLER sound for Guitar and for Bass.
EV "B" use copper voice coils, some mistakenly use them for Bass Guitar but they're sort of muddy, they are meant for PA`woofer duty.

Rail ps caps must be slowly variac'd upwards upwards? Can u just trust the telltale failure rupture indicator nipple thingy?

Looks like we're beyond that stage by now.

When I bought it brand new, as a naiive college student, the slick city salesman selected it based on my financial lowlyness.

The "slick salesman" did you a big favour, doubly so if he sold it for cheap.
Not many amps use EV speakers or are made this good.
Thing Gibson/Norlin L series for the only comparable one in that era.
I was surprised at the quality when I first saw them.

But it sounded very appealing irregardless of class ab topology output.

??? 99.5% amps use "Class AB topology" and the exception are small, low powered, single ended tube amps.
Think 5W RMS class.

Let me get some pics of the preamp solder landings lifted repaired traces, recall pretty severe.

That's more a comment on the Tech soldering ability than on PCB quality (which by the way is very good)

"but i want to reduce poweramp rails from 57dc to 47dc as schematic assigns."

Just play loud

This schematic shows +/-47V DC rails "at full output" which is very honest.

No signal/no load may very well be +/-57V .

A beast of an amp, doubly so driving EVL speakers.

Probably a dream amp for steel players, although it was not specifically intended for that.

EDIT: and that "aquamarine coloured ooze" which worries you so much and which I fail to find in posted pictures, may probably be some coloured nail enamel type paint, usually applied to screws to avoid turning under vibration (think LocTite nut lock) and sometimes over soldered connections to easily detect unauthorized messing with the amp, for warranty reasons.

I've seen amps with every soldered joint painted some particular shade of purple, the reasoning behind that being that if you mess with that soldering, you destroy coloured enamel and you will not get the same at home.

[hewo]

road 5010 lead

1. Thankyou responses all forum members involved
2. Achieved sweet config manipulating controls while assistant tinkered knobs and i kept on tele signaling input.
3. Poweramp dc rails don't droop during live driving of poweramp using sine one k input twentyfive mv and dummy load eight ohm power resistor.
4. Headroom galore, yet do not know if sound can be even sweeter if dc rails lowered to target schematic 47
5. Will ballast caps blindly, starting at two point two k across each ten thousand cap
6. This is blind approach until graph extrapolation reveals value ballast resistor
7. Responses welcome

Oh PLEASE stop overthinking

Starting from the beginning, your amp is working VERY well.

Shouldn't that be a clue?

Won't continue answering until your 29M of pictures or whatever end downloading, so bear with me.

Ok, I'm back.
1) very large but unsharp pictures are not much use, I halved size of yours, sharpened them and ... surprise ... lowered average >3MB *each* to average 200k each
2)
EV "L" use aluminum voice coils, KILLER sound for Guitar and for Bass.
EV "B" use copper voice coils, some mistakenly use them for Bass Guitar but they're sort of muddy, they are meant for PA`woofer duty.


Looks like we're beyond that stage by now.


The "slick salesman" did you a big favour, doubly so if he sold it for cheap.
Not many amps use EV speakers or are made this good.
Thing Gibson/Norlin L series for the only comparable one in that era.
I was surprised at the quality when I first saw them.


??? 99.5% amps use "Class AB topology" and the exception are small, low powered, single ended tube amps.
Think 5W RMS class.

That's more a comment on the Tech soldering ability than on PCB quality (which by the way is very good)

Just play loud

This schematic shows +/-47V DC rails "at full output" which is very honest.

No signal/no load may very well be +/-57V .

A beast of an amp, doubly so driving EVL speakers.

Probably a dream amp for steel players, although it was not specifically intended for that.

EDIT: and that "aquamarine coloured ooze" which worries you so much and which I fail to find in posted pictures, may probably be some coloured nail enamel type paint, usually applied to screws to avoid turning under vibration (think LocTite nut lock) and sometimes over soldered connections to easily detect unauthorized messing with the amp, for warranty reasons.

I've seen amps with every soldered joint painted some particular shade of purple, the reasoning behind that being that if you mess with that soldering, you destroy coloured enamel and you will not get the same at home.