[wthenshaw]

First off I'd like to say if the Mods decide this is in the wrong place go ahead and redirect it, as this isn't computing but is a mod/build in the end of the day and I'd like to share it with fellow OCNers. Thanks in advance.

So after being driven to boredom after finishing my Water Cooled Raspberry Pi build last year I've been searching for a new project. Due to me being a poor student I can't afford to build anything with as much eye candy as the rest of you lot, so I tend to opt for something unique and low cost, focusing on the concept rather than how big a wad of cash I can blow in a week

I have an 1953 Pye P75 Valve radio (long wave, medium wave) in good working condition, but cosmetically is an eyesore. I've had this for over a year now and the first thing I did with it was scrap the cabinet as some of it had been eaten away by whatever infestation (this radio was a barn find).

Originally I was going to make my own housing for it in a theme but the chassis and the majority of components need to be replaced if they are to be displayed purposefully.

Speaking with my Dad we came to the idea of stripping out the majority of the radio and keeping the mains transformer along with the sound output transformer and valves and turning it into an amplifier.

Progressing from there I wanted this to be a little more capable so decided to make this a stereo valve amplifier.

The chassis will be crafted from aluminium and I will be forming it with an aluminium bender and guillotine similar to what I did on my raspberry pi.

The amplifier will accept input from a 3.5mm auxiliary jack or phono input, so I can hook it up to an existing media device. This will be controlled by a toggle switch.

The amplifier will output through either a 3.5mm headphone jack or through a speaker chassis panel in hope that this will drive my Wharfedale E.50s. This will also be controlled by a toggle switch.

I will have 4 potentiometers of varying ohms ratings to control volume, bass, treble and balance.

This build is in the planning stages untill the end of March and I will also be using this time to gather funds for the valves and transformers.

In this month expect to see hand drawn sketches, simple 3D models, and pictures of parts I may accumulate in this time.

As always suggestions and constructive criticism are welcome!

 

[kpoeticg]

Subbed 1st!!!! I win

 

[GaMbi2004]

sub 2nd, I loose

 

[wthenshaw]

Took some photos of the gear I already have for this project. I'll also share some existing photos of the radio that I shall be stripping down entirely in the near future (not sure if I will get it done today).

Battling the dull gear ambient light from the typical British weather, apologies if the quality isn't up to scratch.

Panel light I inted to use as a power indicator. Uses a 6v bulb which will run from the Valve heater voltage.



Speaker chassis panel so I can hook up my Wharfedale E.50s



Mullard pre-amp I am toying with the idea of using for higher gain and easier control over Bass and Treble.




Pictures of the Radio - full album here

http://imgur.com/nyQhQ

Quote:

Originally Posted by kpoeticg

Subbed 1st!!!! I win

Quote:

Originally Posted by GaMbi2004

sub 2nd, I loose

Actually I subbed first

 

[wthenshaw]

This is what the panel light should look like illuminated.



Also took a couple more parting shots of the radio before stripping it down.




tested the old bulb that came with the panel light, good job too. thing turned to milk in a second.

 

[welshy46]

I'm as in as a Russian in a black sea port.

 

[wthenshaw]

Took me a few read through to understand this haha, welcome.

 

[wthenshaw]

Good news update! Won the auction for a Decca SRG707 valve amp and tuner on ebay. This will provide me the valves and sound output transformers, along with the rectifier and mains transformer for my build. Will still have to buy all new resistors and capacitors, and most likely the new potentiometers and definitely the valve bases to give this a new and clean look.

Stay tuned! (Pardon the pun)

 

[wthenshaw]

So, I arrived at my dad's and the first thing I do is pull out the donor radio and take some photos for you guys

Quality will be *meh* as I am just taking photos on the table with sunlight streaming through the window.

Posting to you from my dad's awfully slow laptop, jeez my phone is quicker than this!

Some overview shots






Quick snaps of the undercarriage.



Pristine Mullard EL84! What I like to see

I had no idea on the condition of the donor radio and its valves so I am very happy to see one is such beautiful condition


Second EL84 (This is a stereo amp) is a Mazda, I presume it replaced a faulty Mullard before, as all the rest of the valves in it seem to be Mullard. Once this amp is up and running I may look into replacing the Mazda with another Mullard hopefully in such condition as the first EL84 to match the rest of the AMP

 

[welshy46]

I'll 'fess up, I have no idea what is going on or what you are doing here

but after reading through your last two build logs. I'm v curious. for me, it's all about taking a pre existing product and making it your own. It's easy to take say a huge caselabs case and put a water loop in it, you could train a monkey to do it. This kind of build shows real human ingenuity, for this I applaud you sir.


keep on pushing

 

[wthenshaw]

Thanks bud! In short the plan is to tear down the above radio/amp (donor) to the individual components, build an aluminium chassis and take some components from the donor radio/amp, such as the main and sound output transformers, the sound output and rectifier valves, potentiometers, mount them to the chassis, buy all new resistors and capacitors (as seen on the underside of the donor) and wire the thing up with the inputs and outputs I desire.

I intend to have a clean and retro look on this thing, the vales picture above I cleaned up which is what I want them all to look like, although although I may have trouble cleaning the rectifier valve up

Apologies for photo quality, took this quickly on my Galaxy S4 whilst writing the post.

 

[welshy46]

i got the turning the valve radio into an amp part, it's the having the knowledge to do it bit that got me lol. Especially as you have said previously in another thread. that you're a young student. I'm old enough and poor enough to have grown up with this kind of technology in my youth and I wouldn't have the foggiest on where to start.

Next time I'm up at my parents, I'll take a look in the loft and see if there's anything like this still lurking up there. if there is and it's of any use, you can have it. My Dad never throws anything away, but I'm sure he wouldn't mind parting with it for a worthy cause. I wouldn't be surprised if there is some old valve run radio's or TVs up there. There's still most of mine and my sister's toys up there from like 30 years ago.

I keep meaning to dig out my star wars stuff to bring back down here, all heavily played with in my youth, so not worth anything. Not that I'd part with it anyway. Like Father, like son.

 

[wthenshaw]

My dad will be helping me with the parts I don't know, like following the circuit diagrams

 

[welshy46]

yeah my dad was an electrician, retired now but he does love drawing diagrams of anything he takes apart. I tell him to take photos, but that's how he's always done it.

just got my next project, just bought an original PS3 with backwards compatability and the extra USB ports and card reader. Guy claims it's only had about 20 hours use, will see when I go over to Wakefield to pick it up. not sure how I'm going to get a boxed PS3 and 21 games in a rucksack. Should be a nice trip out on my bike if the weather holds though.

 

[wthenshaw]

Depends on the size of your backpack

 

[welshy46]

It's Republic of gamers shuttle 17" laptop backpack, quite capacious inside. Probs get all the games and peripherals in there and bungie the PS3 box down to the back seat. Just on checking google maps for a twisty route to get there, I'm not a big fan of sitting on motorways on a sportsbike. doing to many straight miles flattens the rear tyre, I've got BSB spec Pirelli Diablo tyres. They do love a good twisty road, nearly as much as I do.

 

[wthenshaw]

Just make sure that PS3 doesn't fling off the seat

 

[Truedeal]

Must you always make such great things?

How much power do you think this is supposed to provide to your Wharfedale

 

[wthenshaw]

Not entirely sure how this will handle, from what I read online it will deliver reasonable power. So long as I can have comfortable listening levels then it wasn't a failure

 

[welshy46]

Quote:

Originally Posted by wthenshaw

Just make sure that PS3 doesn't fling off the seat

I'm more concerned about me flinging off the seat lol. I'm going over to pick it up tomoorow, just hope the weather holds. I'll be taking the scenic route over woodhead pass

proper biking road