Build 5F2 clone (Thread)

[Tintinus87]

Hello, I put here my 5F2 clone building advancement.

I bought a kit from Tube-Town, which is not very expensive and give a lot of stuff (screw, etc, etc). I changed carbon film-resistor and mallory capacitor of the kit by carbon comp and jupiter capacitor for a little "mojo" tone (not very expensive too by the feww component in the amp).
The kit from tube town have a nice quality solder board, with a ground bus, and it is similar to the 5F1.

The schematic is a little different of the others kit, as TAD for exemple there is no choke and only 15-10-10 capacitor.
The main power supply in the kit is not the 5e3-vpo of the schematic but the Hammond 291AEX which have choice 275-0-275 VAC secondary voltage that I will use.
The vaccum tube are a Sovtek 5Y3GT (a special tube who do not look like than any other tube, indirect heated and have a little drop voltage 18V in 100mA) , a JJ 6V6S and JJ ECC83S.

On the schematic below I added a backup rectifier diode on the pin 4 & 6 of the 5Y3GT (I have NOS 5W4GT - a low power 5Y3- that maybe I use instead)




And I add also a SPDT switch for the primary output transformer impedance (5K or 8K) and a second jack for a 16 ohm speaker.



Indeed I bought a pin cab on Tube-Town, Tolex it with "tweed vinyl" Tolex (not real tweed but very nice) and installed inthere a WGS G12Q 12" 20W.




So after making the cabinet, I started to solder component and I just finish the board today

The chassis is very tight and it is a hard challenge too place all the wire, specially the multiple useless wire of the main power transformer !!

That's it for now !

 

[King Fan]

Looks nice. Tres jolie, in my non-existent French. You're right, the tiny narrow chassis is a challenge. FWIW, here's a tidy wiring job with lots of pics I found in an image search...

https://www.offsetguitars.com/forums/viewtopic.php?f=10&t=122228&start=15

Sample:

But on closer inspection, I wonder if the TT chassis is even smaller than Fender's. Either that or they gave you really fat wire. Wow, formidable *and* formidable.

 

[YellowBoots]

And I add also a SPDT switch for the primary output transformer impedance (5K or 8K) and a second jack for a 16 ohm speaker.

What does the hive mind think about this? Is it any more unsafe than a standby switch? What about fly back on the OT? Put the switch in the chassis and limit the use to amp off only? I’m all questions and no answers.

 

[Tintinus87]

Thanks for the link the chassis that he use I think is slighty larger than mine. And his main power transformer have less much wiring it help a lot

 

[Tintinus87]

What does the hive mind think about this? Is it any more unsafe than a standby switch? What about fly back on the OT? Put the switch in the chassis and limit the use to amp off only? I’m all questions and no answers.

I just add a switch because I don't want to solder and dessolder the wire, and on some shematics :
-On Tube amp doctor kit, 8K2 primary with 4 ohm output and 22k NFB on 4ohm tap,
-On Tube town kit, 5K primary with 8 ohm output and 22K NFB on 8 ohm tap
- On Mojotone kit, 7k primary with 8 ohm output and 22K NFB on 8 ohm tap
-On Weber kit, 8k primary with 8 ohm output and 22K NFB on 8 ohm tap

and I only use switch when the amp is not powered.

 

[Peegoo]

Wow.

Very wow! Nice work...and the cabinet too!

 

[chas.wahl]

That TubeTown chassis is definitely a lot smaller than the standard Fender size -- look at the control cutout in the cabinet, and the spacing between components on the control side.

You can cut wires to a shorter length to reduce the clutter inside the chassis; just not too short. And if your power transformer is a dual-primary-voltage type, then two of those wires will simply be connected together, so that will de-clutter a bit too. Plus, if you have a dual-secondary-high-voltage transformer (like 330-0-330 or 325-0-325 plus 275-0-275, which you say you are using) and you don't ever care to use the higher voltage, then you can cut those wires short too. Just make sure you insulate the ends of any cut wires, and don't cut them so short that you cannot later strip and put a splice on them to use them if needed!

As everyone else is saying: trés bonne fabrication!

 

[leewongfei]

Try to clean up some of that flux. It looks like a lot of it spread while soldering. ALL FLUX IS CORROSIVE, especially on PCB's. Even the no-clean stuff can be corrosive in large amounts if its not burned up or cleaned completely. The flux is a big part of what smokes when soldering, thats why its important to only use as much as you need. A Q-tip or brush and some rubbing alcohol will get the majority off and neutralize the unburned flux.

Here is a link to a page with more information:
Why you should clean flux

 

[Tintinus87]

That TubeTown chassis is definitely a lot smaller than the standard Fender size -- look at the control cutout in the cabinet, and the spacing between components on the control side.

....

As everyone else is saying: trés bonne fabrication!

I measure TT chassis : 26 cm (the same size of TT 5F1 chassis ) and the "TAD" or old 5F2 chassis are larger : 34.9 cm.

Try to clean up some of that flux. It looks like a lot of it spread while soldering. ALL FLUX IS CORROSIVE, especially on PCB's. Even the no-clean stuff can be corrosive in large amounts if its not burned up or cleaned completely. The flux is a big part of what smokes when soldering, thats why its important to only use as much as you need. A Q-tip or brush and some rubbing alcohol will get the majority off and neutralize the unburned flux.

Here is a link to a page with more information:
Why you should clean flux

Thanks for your answer and link I totally forgot to wash my "no-clean" flux. I did it yesterday night (with special flux remover), some sticky but all the flux is neutralized (even marks on main filter capacitor removed !)

 

[Tintinus87]

The wiring is finished. I have to measure the voltage.

 

[Tintinus87]

Hello, I just finish my amp.
All is very fine and I made some measurements with :
- two rectifiers : a 5y3GT Sovtek (of the kit) which have low drop voltage
- A 5W4GT rectifier which have a real NOS 5Y3 drop voltage
- A 6V6S JJ (of the kit)
- A NOS 6V6GT Raytheon

Both 6v6 have the same specifications (I have a lamp tester)

And with 5K primary and 8K primary output transformer, and WGS12Q speaker.

The test of sound is with a Telecaster and bridge pick-up (alnico old).

First of all :

1) The best sounding amp is the combination : 5W4GT + 6V6GT Raytheon and with 8K primary output transformer. The 8K primary have a clearer, sparkle and more detailled sound, the break-up is better. The 5K is more muffled.

2) The 6v6JJ is good but the main default is the rattle sounding !!!! Do not use this in a combo.

3) The Use of Sovtek 5Y3 increase the voltage, and the amp sounding is very different. The Headroom is very important and the amp have a very difficult for break-up. But for a cleaner amp this can be useful.

4) Even with the use of carbon comp resistor, there is no Hiss and the amplifier is very quiet. The is no "buzz" sound.

Here is the measures with differents combinations. I use "12W" for the NOS 6V6 and 14W for the JJ 6V6.

We find that the plate voltage is higher with 5K primaray output, but not with 6V6GT Ratheon (I don't know why).

Some peoples prefers a higher voltage with 5F2.

I ask to community : what is your plate voltage in your tweed 5F1 or 5F2 ? Which do you prefer ?

The final combination

 

[Tintinus87]

Ah, and a TIP for primary main transformer voltage.
At the beginning I used 120-0-110 VAC for the primary main transformer but my wall voltage is between 235 and 238 VAC, so the heater voltage was too high : 5.4 VAC for rectifier and 6.8 VAC for tubes. I switch to 120.0.120 VAC and the voltage were therefore normal (5.1 VAC and 6.3 VAC). The B1+ were also higher (15V more).

 

[mountainhick]

Hello, I just finish my amp.
All is very fine and I made some measurements with :
- two rectifiers : a 5y3GT Sovtek (of the kit) which have low drop voltage
- A 5W4GT rectifier which have a real NOS 5Y3 drop voltage
- A 6V6S JJ (of the kit)
- A NOS 6V6GT Raytheon

Both 6v6 have the same specifications (I have a lamp tester)

And with 5K primary and 8K primary output transformer, and WGS12Q speaker.

The test of sound is with a Telecaster and bridge pick-up (alnico old).

First of all :

1) The best sounding amp is the combination : 5W4GT + 6V6GT Raytheon and with 8K primary output transformer. The 8K primary have a clearer, sparkle and more detailled sound, the break-up is better. The 5K is more muffled.

2) The 6v6JJ is good but the main default is the rattle sounding !!!! Do not use this in a combo.

3) The Use of Sovtek 5Y3 increase the voltage, and the amp sounding is very different. The Headroom is very important and the amp have a very difficult for break-up. But for a cleaner amp this can be useful.

4) Even with the use of carbon comp resistor, there is no Hiss and the amplifier is very quiet. The is no "buzz" sound.

Here is the measures with differents combinations. I use "12W" for the NOS 6V6 and 14W for the JJ 6V6.

We find that the plate voltage is higher with 5K primaray output, but not with 6V6GT Ratheon (I don't know why).

Some peoples prefers a higher voltage with 5F2.

I ask to community : what is your plate voltage in your tweed 5F1 or 5F2 ? Which do you prefer ?



View attachment 1099991

The final combination

View attachment 1099988

Thanks for the thoughtful analysis of these differences along with voltage charts!