Two articles are missing:
Those folded PCB with machine inserted wire jumpers were very low manufacturing cost (you're welcome). Those machine made jumpers come from a single reel of solid wire on the jumper machine and got cut to length during insertion. Of course solid wire will fatigue and break if you bend it too many times, so don't do that.Two articles are missing:
Chapter 8 - How sorry we are for ever producing three-dimensional folded origami PCB's interconnected with breakable wire jumpers
In the early days of SMD (last century) we mixed pots and switches on the top of a flat budget mixer PCB, with active and passive SMD components on the bottom (solder side) of the PCB, for very low manufacturing costs and affordable SKU pricing (you're welcome).Chapter 9 - How we saved three-tenths of a cent by burying all commonly-replaced parts on the bottoms of PCB's inaccessible to the user
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Opinions vary on that. Lower manufacturing cost is powerful when designing value products for price conscious customers.There is no justification to ever make up for doing it that way, no matter what Hartley told you.![]()
FWIW Back in the good (very) old days the iconic CS power amp series were definitely engineered for repairability with some packaging costs added just to improve serviceability. Near the end of my time there, market competition made such superfluous costs uneconomic. Customers don't care about repair cost at point of sale.Case in point: here's a pic of me trying to repair someone's beloved Classic 30:
In the early days of SMD, many parts were not available in SMD and even if they were they were often very expensive. So almost all designs were part SMD , part through hole. Hence though hole on top and SMD on the underside of the PCB.In the early days of SMD (last century) we mixed pots and switches on the top of a flat budget mixer PCB, with active and passive SMD components on the bottom (solder side) of the PCB, for very low manufacturing costs and affordable SKU pricing (you're welcome).
JR
Chapter 8 - How sorry we are for ever producing three-dimensional folded origami PCB's interconnected with breakable wire jumpers
JR didn't design guitar amps, but I copied the machine inserted jumper, wave soldered flat, then bent up PCB strategy (because I'm frugal). I'm not a guitar amp guy. IIRC the classic series were pretty well respected for their sound, the 30 was probably the smallest and therefore the sharpest pencil design exercise of the entire series.I chuckled when I saw that, because the Classic 30 was precisely what I'd immediately thought of when I read your earlier post:
The Classic 30 is nice sounding amp, but nightmarish little things to work on, they are. Actually, nightmarish little things they are just to get out of the cabinet in one piece without breaking the jumpers, let alone actually work on.
Bad JR. No dessert for you.
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Thus proving that I am not the guitar amp guy.There was also a Classic 20 model in the series. In 1994 I played a really nice Rickenbacker 1997 ("export" model 330 reissue) through one at Guitar Showcase in SJ. Shoulda bought both!
I'm confident that it was not made difficult to service on purpose. It was made inexpensive to manufacture and the servicing difficulty was an unintended negative consequence.Any time I open a piece of gear that is made difficult to service I'm thankful that my main amps are classic Fenders.
I'm 90% sure the design was from James Brown, because I recall watching an interview with him on YouTube (I think it might be the Tone Talk podcast...the one with Dave Friedman) where I think James apologized for the design. So I guess all is forgiven. I do understand that repairability 40 years down the road probably wasn't of utmost importance at the time. It is a testament to the tone that people are willing to put up with a nightmarish repair to keep them going.The Classic 30 is nice sounding amp, but nightmarish little things to work on, they are. Actually, nightmarish little things they are just to get out of the cabinet in one piece without breaking the jumpers, let alone actually work on.
Yes, but Fenders were made easy to service because Leo started out in the radio repair business and grokked that factor. Design for serviceability does not have to be uber expensive, but it should be considered more often than it is. But with MBAs and bean counters running everything...here we are.I'm confident that it was not made difficult to service on purpose. It was made inexpensive to manufacture and the servicing difficulty was an unintended negative consequence.
and Peavey's were engineered to be easy to service too, back when. That calculus fell apart when several manufacturers moved production offshore (or to Mexico) making it impossible to compete heads up building gear in US factories. I have known a handful of people who worked at Fender either before or after Peavey gigs.Yes, but Fenders were made easy to service because Leo started out in the radio repair business and grokked that factor. Design for serviceability does not have to be uber expensive, but it should be considered more often than it is. But with MBAs and bean counters running everything...here we are.
Cheap and repairable.To be fair Fenders were also made for a price point with the cheapest materials that could be found:
I hear those stories, but haven't had any trouble with the waxed eyelet boards in my three silver faces that are pushing 50 years. I got them second hand (or more) and they've lived indoors with climate control since then ('91, '95, and '08). Maybe the problems come from storage in garages, basements, sheds, etc.wax impregnated cardboard with brass eyelets from jeans wasn't exactly the best way to make something that survived the ages, but it sure was cheap.. Especially now, when the boards leak voltage everywhere after absorbing 60 years of moisture and cigarette smoke and becoming conductive.
Can't argue with that. If I ever get around to it, I want to gut my red knob Champ-12 and build something better in the chassis. I'll use fiberglass or phenolic tagboard or turretboard.The ultimate for repairability (IMHO) is a 3" strip of 1/8" (125mil) Garolite XX (paper-reinforced phenolic resin sheet) with Marshall-style swaged turrets. Anytime I need to restore a 60's Fender this is what I use. It's rated at 40kV dielectric breakdown voltage, and has a bulk impedance of 10MEG / mil and doesn't absorb moisture, and tolerates being soldered without deforming (so long as you down leave the iron on the turret all day). PTFE sheets also work really well for this.
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