fender Blues DeLuxe Reissue ate two PT,s fuse not blown and correct value

[Jazz P Bass]

[QUOTE=Alan0354;351178]I don't agree with putting in fuse thing. To me, it's just ways to get money from the user. They should use the main fuse as the one to blow. QUOTE]

Over the years, it has become apparent that a transformer that has been overstressed, while still capable of functioning, for safety reasons, it should be removed from service.

Hense the internal (infernal?) fuseable link.

The big question is "was the fusable link up to the task or did it fail prematurely?"

[Jazz P Bass]

I had a GK amp, with a 'master volume' setup.
The MV pot was damaged & went beyond the stop detent & went open circuit.
Red Plate City!

[J M Fahey]

I had a GK amp, with a 'master volume' setup.
The MV pot was damaged & went beyond the stop detent & went open circuit.
Red Plate City!

Well, that would be a real achievement, considering there are no tube GK amps

[Alan0354]

[QUOTE=Jazz P Bass;351225]

I don't agree with putting in fuse thing. To me, it's just ways to get money from the user. They should use the main fuse as the one to blow. QUOTE]

Over the years, it has become apparent that a transformer that has been overstressed, while still capable of functioning, for safety reasons, it should be removed from service.

Hense the internal (infernal?) fuseable link.

The big question is "was the fusable link up to the task or did it fail prematurely?"

But the manufacturer is the one that choose the PT, how can they choose an under rated PT for the job to start with and then put in a weak link inside so the PT blow out?!!!

I don't think we are talking people modding the amp and use more power here.

But from reading, Fender does not design the new amps with margin like the old Fenders. I was helping in fixing the Super Sonic, they use opamp as relay drivers!!! They use single sided pcb with no plated through holes!!! Any stress on the pcb will rip the trace out!!! I think people should buy the old SF and BF amps, service them and use them instead. They are so much more reliable.

[JoeM]

But the manufacturer is the one that choose the PT, how can they choose an under rated PT for the job to start with and then put in a weak link inside so the PT blow out?!!!

I don't think we are talking people modding the amp and use more power here.

I think you're making an assumption the PT is under-rated. Fender sells one heck of a lot of the HR series amps, statistically, what percent of these actually fail? The problem with the +/- 16v supply is probably a lot more common.

[Alan0354]

Wait!!!

OP did not specify whether he replace the burned PT with the original Fender PT. This is very important, if the second PT is a after market, then the problem is likely to be in the amp.

[Jazz P Bass]

Got me.
I'll have to look up the amp.

[Alan0354]

I think you're making an assumption the PT is under-rated. Fender sells one heck of a lot of the HR series amps, statistically, what percent of these actually fail? The problem with the +/- 16v supply is probably a lot more common.

Well, if he amp is not modded, and it burn two transformers. IF....and I repeat....IF both are Fender OEM PT, one can assume the transformer is under power.

That's the reason I kept saying, open the transformer and look. We are all guessing here.

[J M Fahey]

[QUOTE=Alan0354;351235]

But the manufacturer is the one that choose the PT, how can they choose an under rated PT for the job to start with

Ever heard about cost cutting?
And I'm not talking about Fender specifically but any manufacturer who wants to sell in the open, competitive market.
99% manufacturers are cost conscious and maybe 1% cater to snobs or people who will pay significantly more above market price.
In fact Fender (same as Peavey and many others) has succeeded in making a very good product for a very competitive price, kudos to them.
To boot, I'd say that maybe 1% of them has problems.
Of course, if you make 6000 HRD and similar amps a Month, 1% means a few now and then .... so what about the trouble free 99% ?
It's the angry customers who vent in Internet Forums, Yelp, etc. so you get to read them.

and then put in a weak link inside so the PT blow out?!!!

You've got it *absolutely* wrong.
The safety device (which you maliciously call "weak link") is not there "to make the PT blow" (what a paranoid delusion) but to avoid it melting and catching fire, ultimately burning your house down or worse.
You don't want it to open that primary winding? ..... then don't let your PT overheat to plastic melting, insulation burning levels. Period.
And since people often do stupid things, sometimes out of ignorance, sometimes out of recklessness (hey!! , I'm playing like a killer Guitar God tonight!!! , I'll ignore that molten varnish smell coming from my amp and play some more of my fabulous licks !!! ) then *Safety Agencies* (not Fender themselves) now demand those safety devices built in.

But from reading, Fender does not design the new amps with margin like the old Fenders.

Nobody does.
In the old days, people willingly payed 4 monthly salaries for an amp, then kept it for many years; today people pays $700/800 for an HRD , less than 1/4 salary !!!!!!!!!!!!!!!!!!!!!!!!!!
And they get GAS so next month they buy an Egnater, 2 months later a Randall, and so on.
Then people post or sign: "I have 17 (cheap) guitars , 9 (cheap) amps" and so on.

I was helping in fixing the Super Sonic, they use opamp as relay drivers!!! They use single sided pcb with no plated through holes!!! Any stress on the pcb will rip the trace out!!!

Regular automated factory mass production Fenders are impressive, doubly so at the price.
Custom Shop products are there only to be able to claim some "special " products are available, to satisfy a few important Musicians and some snobs.
Being almost handmade and in very small quantities often do not justify advanced assembly or even modern PCB which are reasonably priced only in large quantities.
Consider Custom Shop products MUCH closer to homebuilder/small Luthier stuff (so similar small scale production technology) than the professional Fender main line.
Single face non PTH PCBs? LOL, they look like my own amps
Proudly made in a couple rooms in an old house

I think people should buy the old SF and BF amps, service them and use them instead. They are so much more reliable.

Well, they will be more reliable *after* you replace all those dead electrolytics, leaking old capacitors, clean/replace all dirty/worn/rusty/you_name_it jacks, pots and switches.
Ah !! don't forget to retension those tube sockets .
Or better replace them, I wouldn't trust their contacts that much, specially since they are *already* 50/60 years old.

FWIW and if preferring old technology and ease of service, I'd get one good modern kit such as a Ceriatone (they look real well made) , and build my own.
Best of both worlds: oldtime simplicity and reliability (don't mistake me, I also like that) coupled to fresh parts, of which I can select and upgrade any before actual construction, and ... fresh out of the oven !!!

[Mark Black]

Too bad the OP seems to have done a "hit-and-run".

[Alan0354]

[QUOTE=J M Fahey;351242]

Ever heard about cost cutting?
And I'm not talking about Fender specifically but any manufacturer who wants to sell in the open, competitive market.
99% manufacturers are cost conscious and maybe 1% cater to snobs or people who will pay significantly more above market price.
In fact Fender (same as Peavey and many others) has succeeded in making a very good product for a very competitive price, kudos to them.
To boot, I'd say that maybe 1% of them has problems.
Of course, if you make 6000 HRD and similar amps a Month, 1% means a few now and then .... so what about the trouble free 99% ?
It's the angry customers who vent in Internet Forums, Yelp, etc. so you get to read them.


You've got it *absolutely* wrong.
The safety device (which you maliciously call "weak link") is not there "to make the PT blow" (what a paranoid delusion) but to avoid it melting and catching fire, ultimately burning your house down or worse.
You don't want it to open that primary winding? ..... then don't let your PT overheat to plastic melting, insulation burning levels. Period.
And since people often do stupid things, sometimes out of ignorance, sometimes out of recklessness (hey!! , I'm playing like a killer Guitar God tonight!!! , I'll ignore that molten varnish smell coming from my amp and play some more of my fabulous licks !!! ) then *Safety Agencies* (not Fender themselves) now demand those safety devices built in.

Nobody does.
In the old days, people willingly payed 4 monthly salaries for an amp, then kept it for many years; today people pays $700/800 for an HRD , less than 1/4 salary !!!!!!!!!!!!!!!!!!!!!!!!!!
And they get GAS so next month they buy an Egnater, 2 months later a Randall, and so on.
Then people post or sign: "I have 17 (cheap) guitars , 9 (cheap) amps" and so on.

Regular automated factory mass production Fenders are impressive, doubly so at the price.
Custom Shop products are there only to be able to claim some "special " products are available, to satisfy a few important Musicians and some snobs.
Being almost handmade and in very small quantities often do not justify advanced assembly or even modern PCB which are reasonably priced only in large quantities.
Consider Custom Shop products MUCH closer to homebuilder/small Luthier stuff (so similar small scale production technology) than the professional Fender main line.
Single face non PTH PCBs? LOL, they look like my own amps
Proudly made in a couple rooms in an old house


Well, they will be more reliable *after* you replace all those dead electrolytics, leaking old capacitors, clean/replace all dirty/worn/rusty/you_name_it jacks, pots and switches.
Ah !! don't forget to retension those tube sockets .
Or better replace them, I wouldn't trust their contacts that much, specially since they are *already* 50/60 years old.

FWIW and if preferring old technology and ease of service, I'd get one good modern kit such as a Ceriatone (they look real well made) , and build my own.
Best of both worlds: oldtime simplicity and reliability (don't mistake me, I also like that) coupled to fresh parts, of which I can select and upgrade any before actual construction, and ... fresh out of the oven !!!

Are we talking about a stock amp or modded amp. If it is stock amp, there is no reason to over heat under normal condition if it is designed right. The main fuse should take care of it.

Fender don't do home made pcb. There is no difference between a ingle layer and two layers board. The cladding comes in 2 layers. You have to etch out the one layer to intentionally make a single layer board. Cost is NOT a reason. Plate through holes make the pcb so much more reliable.

[J M Fahey]

[QUOTE=Alan0354;351254]

Are we talking about a stock amp or modded amp. If it is stock amp, there is no reason to over heat under normal condition if it is designed right. The main fuse should take care of it.

The mains fuse is current sensitive and takes care of plain shorts, both in the transformer itself and after, such as a shorted rectifier or main filter cap or blown tube or lost bias.
The *thermal* fuse takes care of *thermal* problems inside the transformer, a.k.a gross overheating.
Both problems do not necessarily happen at the same time, so both protection systems are NOT redundant but complementary.

Fender don't do home made pcb.

How do you know?
And by the way, I didnīt say *homemade* buy meant very small scale production, where it often does not pay to use the big scale supplier ... and the high Technology he might use in a big order.
And you confirmed it yourself.
Wasnīt you who talked about a single face non PTH board PCB?
I have seen guts of Custom Shop Fender amps where the insides looked like somebody poured their pasta bowl inside , THAT poor and messy was the wiring.
This is an expensive Custom Shop product, the Fender Tone Master:

Looks **very** homemade to me.
Not talking about the PCB (although it also looks quite homemade) but the messy wiring and layout.
Including the very poor board layout, because it should have been designed to minimize that messy wiring.
Or worse, because I have seen tons of homemade amps much better wired than this mess.

There is no difference between a ingle layer and two layers board.

No kidding!!!!

The cladding comes in 2 layers. You have to etch out the one layer to intentionally make a single layer board.

You have no clue about PCB manufacturing.
Thereīs single layer PCB material and thereīs 2 layer.
Single layer is cheaper.
Buying 2 layer and eating the unused one is stupid on 3 counts:
a) itīs more expensive
2) it takes longer, you add not 1 extra unnecessary step but 3 to 5, because you have to etch , wash and dry your PCB to continue with the layer that stays.
3) you waste a lot of etchant and contaminate the Earth, needlessly.
Did I say that *this* is also very expensive?
Much more than the simple price difference between 1 and 2 layer.

Cost is NOT a reason.

Bet you never owned a shop or managed costs in one I guess.

Plate through holes make the pcb so much more reliable.

Now we agree on something

[Alan0354]

[QUOTE=J M Fahey;351274]

You have no clue about PCB manufacturing.
Thereīs single layer PCB material and thereīs 2 layer.
Single layer is cheaper.
Buying 2 layer and eating the unused one is stupid on 3 counts:
a) itīs more expensive
2) it takes longer, you add not 1 extra unnecessary step but 3 to 5, because you have to etch , wash and dry your PCB to continue with the layer that stays.
3) you waste a lot of etchant and contaminate the Earth, needlessly.
Did I say that *this* is also very expensive?
Much more than the simple price difference between 1 and 2 layer.

Bet you never owned a shop or managed costs in one I guess.

Now we agree on something

Excuse me!!! I do a lot of pcb layout and know a lot about pcb. I design stack up on all different number of layers up to 26 layers. Claddings comes as two layers. I visited and talk extensively with pcb manufacturers on how to do stack up on pcb. Modern days FR4 comes in two layers of copper and they have to etch out the first layers. I know because I design control impedance layout that I actually had to design the spacing between layers and I need to know all the available thickness options. I even do mixed materials like combining Rogers with FR4 in the stackup.

I just layout a few pcb and sent them to Hong Kong to manufacture, they are cheap. Your info is too old, now a days, nobody do single layers, at least 4 layers on up. Price dropped tremendously compare to 20 years ago because the technology is so much more advance. I just did 5 of the two layers 2"X1.3" pcb run for $50 and free shipping. It will cost hundreds of dollars 25 years ago!!! You calculate the cost by how it fit on one panel.

[Alan0354]

Are you still etching your own pcb?!!! You better get on ebay and check out the price of pcb!!!! Buy the Eagle pcb layout and schematic for a few hundred dollars, learn how to do layout!!! Then you just sent the Gerber file and you'll get cheap pcb in two weeks!!!

I am even debating whether I want to hand wire my prototype amp or just layout the pcb from the get go. So I can eliminate the uncertainty of whether the production pcb will have the same performance as the prototype.

[J M Fahey]

[QUOTE=Alan0354;351280]

Excuse me!!! I do a lot of pcb layout and know a lot about pcb. I design stack up on all different number of layers up to 26 layers. Claddings comes as two layers.

Excuse you nothing.
You have no clue.
Tell that to Farnell, CAA20 - CIF - EPOXY FR4 KIT, 1F, 10PC, 200X300 | Farnell Israel who sells you as much as you want of SINGLE face virgin PCB material.

And I repeat that buying 2 face and etching one off is stupid and irresponsible.

By the way, it's what a NOOB would do if he needed to make one small single face PCB and local Radio Shack only carried 2 face.

I visited and talk extensively with pcb manufacturers on how to do stack up on pcb. Modern days FR4 comes in two layers of copper and they have to etch out the first layers.

See Farnell page above about singlelayer PCB material.
And repeat that etching 1 layer off just to make single layer material is stupid and irresponsible.

I remember one Simpsons episode where Homer Simpson (not exactly the brightest guy on Earth) melt a lot of ham (discarding the meat) just to collect the grease and sell it by the pound to a soap maker.
Same thing.

I know because I design control impedance layout that I actually had to design the spacing between layers and I need to know all the available thickness options. I even do mixed materials like combining Rogers with FR4 in the stackup.

Really?
And anyway, what do RF constraints have to do with (audio) guitar amps?

I just layout a few pcb and sent them to Hong Kong to manufacture, they are cheap.

Cheap?
Ok, it's your money, why would I worry?

Your info is too old, now a days, nobody do single layers, at least 4 layers on up.

Nobody?
For one my DVD player (made by the millions) uses single face.
My PC speaker amps (also made by the millions) also uses single face.
And millions of other consumer products.
*Only* 4 layers up?
You live in a dream world.

Price dropped tremendously compare to 20 years ago because the technology is so much more advance.

Prices dropped, so what?
I can still beat any "outside made" price, for the exact same reason that a home fried egg is always cheaper than same egg at any diner, no matter how sleazy it might be.

In case you don't get it, at home I play flat cost while any commercial stuff carries added profits, freight and other expenses.
Which also increase tax, by the way.

Of course, if you can not fry an egg, you'll have to go somewhere and order one.
And pay extra for the convenience, of course.

I just did 5 of the two layers 2"X1.3" pcb run for $50 and free shipping. It will cost hundreds of dollars 25 years ago!!! You calculate the cost by how it fit on one panel.

I almost choked on my coffee by reading that.
They are robbing you at gunpoint and you find it cheap?

Let's do a little Math:
2"x1.3"x5=13 sq inches for $50 means you pay 50/13=3.85$ a square inch of ready made PCB
Do we agree so far?

Ok, here's one batch of 36 (count'em) Fahey 100W power amps and +/-42V PSU and +/- 15V preamp supply.
Each 3"x4"=12 sq in.


Going by your "incredibly cheap cost" they should cost 12x3.85=46$ EACH (don't nitpick on the cents, I'm rounding to nearest value).
So those 36 boards should cost 36x46=1656$

Is my Math wrong?
Does your calculator show different results?
If so, post them.

Now to MY costs:
for reference here's the US price of a full sheet , 3 by 4 feet or 37"x49" CEM1 single face copperclad material.
CEM-1 .059 2/0 37? x 49?
a whopping $30
That's the US price, in packs of 5 sheets .

Since I am in Argentina, have to add import tax and as I buy just by the single 3x4 ft sheet, I pay U$84 for it.

Since it measures 37x49=1813 sq inches, my raw base material cost comes to 84/1813=0.047 $/sq in.

So each PCB will use 0.047x12=0.57$ worth of laminate.

36 PCB will use 36x0.57=20.5$

Add to that, say, 5$ ink, 5$ cleaning solvents, 5$ ferric perchloride, 5$ electricity or whatever, we have a grand total of 40$ for 36 ready to solder PCB .

Your Hong Kong supplier would have charged, as calculated above: 1656$
So I am saving 1656-40=1616$
For the added cost of one full day work.
Oh .... and I had to LEARN how to do it

And *I* am the fool ?

Don't worry, no hard feelings, I must remember you never run your own shop so you were always shielded from the harsh realities of life.

Unfortunately, I'm not an Electronics Engineer but an Industrial Engineer, with 43 years non stop running my own successful business, keeping it alive through lots of Crisis , so forgive me if I focus "a little too much" on production cost and simplicity instead of the transmission line properties at 1 GHz of common guitar cable material