Mini Heterodyne Receiver

Very nice, very tidy inside! I've been putting off my first SMD opportunity.. keen to break the seal soon, though! Do you have one of those special iron tips with the solder 'reservoir'? Do you think I can drag solder with just a chisel tip?
 

DannDubbleEwe

New member
Thanks! I just used the smaller, very long conical tip for my Weller. I put a tiny amount of solder on one pad, tacked the chip on, and slowly made my way across each leg. I think flooding and dragging would be a little cumbersome because the chips are a little “large” for what they are, but I’m brand new at this and hopefully someone else can chime in.
 
Note, FWIW, I recently assembled an FV-1 board (Octagon). This was just one SMD part to do, so I opted to try out low temperature solder paste from adafruit with a hot air rework station. This worked successfully for me. No special tape required to hold it down. I had one unwanted solder bridge which was fixed with some desoldering braid. I find the key is to use a small continuous dab. A little goes a long way.

That shimmer effect is a sweet ambient sound.
 
Note, FWIW, I recently assembled an FV-1 board (Octagon). This was just one SMD part to do, so I opted to try out low temperature solder paste from adafruit with a hot air rework station. This worked successfully for me. No special tape required to hold it down. I had one unwanted solder bridge which was fixed with some desoldering braid. I find the key is to use a small continuous dab. A little goes a long way.

That shimmer effect is a sweet ambient sound.

Cool! Hot air rework station looks like the way to go! What type of temperature do you need to use? Looks like you can get rework stations reasonably cheaply (~$60) I think I might look into that, thanks :) yes I have a ThreeVerb and love it! I obviously opted for pre-soldering tho ;)
 
Cool! Hot air rework station looks like the way to go! What type of temperature do you need to use? Looks like you can get rework stations reasonably cheaply (~$60) I think I might look into that, thanks :) yes I have a ThreeVerb and love it! I obviously opted for pre-soldering tho ;)

I recall I used roughly medium-high air flow and medium to medium-high temperature (your mileage may vary). You can start the temperature on medium and turn it up as needed. This should be a forgiving approach since the heat is being applied indirectly. I have the hot air rework station that is on the sparkfun site. :)
 

nosamiam

New member
Nice looking pedal! I drag soldered mine using a hoof tip and it worked well. I'll have to put up some pics too.

One question: Do you get a ticking sound when you turn up the Oscillator knob (I think that's what it's called; top right knob)? Mine ticks annoyingly when I'm not playing. When I do play, it kind of blends in or goes away.
 

DannDubbleEwe

New member
I’ll have to check later but I know when maxing the modulate knob it stops the LFO in a way. I haven’t had any ticking in bypass. It is a pretty unruly beast so I would expect some ghost sounds happening pretty often while engaged.

One thing I’ve noticed is each sound - sub, square, osc - are very loud so be careful!
 

nosamiam

New member
Oh yes, it is definitely LOUD! I'm guessing it's probably just my pedal. I may have a wrong resistor or cap somewhere. I wish the schematic was available.
 

DTested

New member
Hoping DannDubbleEwe is still lurking... I just finished this yesterday, and -think- it's working. Just wanted to check something though. It's definitely a lot glitchier than I was anticipating. All the controls seem to do something, but I wanted to check something basic.

Do you get any sound from the Sub and Osc level controls when the Square control is at minimum? The Sub in particular. With the Square down, and the sub maxed, you just get some low volume glitchy noises that dont track with input, and I'm not sure if this is correct operation.

My assumption is that you need to have the Square level up a little to get the sub and osc sides to do anything meaningful, but want to check.

Also, and this may or may not be relevant, but I used 1uF 35V Tantalums as that's all I had in the parts box that would fit the spacing. They are polarised, where the circuit expects MLC NP, but I don't think that's an issue. Is it?

Also, I'll toss my vote in for a schematic. Even if it's only to ppl that purchased the PCB. I'm pretty sure I've built this error free, but would love to be able to confirm!!!
 

CanadianDave

Active member
Yo, the subtle differences in the knob colors and the utilitarian look is really cool.

And respect for tackling SMD soldering. I’m still not confident enough.
 

zenhunter72

New member
Just started this, got my SMD's on but trying to figure out what 1uf caps to use. I was going to try shoving some film caps in there and bend the leads but man the spacing is tight! I noticed you used the blue ceramics, do they sound groovy? Seems like there's not room for film caps between all those switches and resistors...
 

DannDubbleEwe

New member
They are multilayer ceramic caps - I think there are some in the shop here but they’re out of stock. I got mine from Mouser.
 
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