Hy gain Vlll mods

[Staybolt]

Any mods for this radio as in open the clarifier and what crystals do I need to get it on cut 36 to 40?

 

[midnight special]

back in the day most guys just got a hygain 675 vfo and kit to wire in and cut the "yellow" wire to use vfo in transmit,,,

 

[hpssb]

Do the full DDS conversion and have all 40 or a ton more if that's your thing


Cobra 29 channel block


Channel display wired up to it


DDS board fitted (visible under covers just behind the toggle switches)


Finished radio ready to use.

NB switch rewired for 5KHz dropper
ANL switch rewired for +10KHz shifter
PA switch rewired for Hi band (27.415-27.855)
Clarifier unlocked and extended to +/- 2.5Khz

Apart from the above, radio is standard...

Loz!

 

[Staybolt]

Do the full DDS conversion and have all 40 or a ton more if that's your thing

View attachment 64451
Cobra 29 channel block

View attachment 64452
Channel display wired up to it

View attachment 64453
DDS board fitted (visible under covers just behind the toggle switches)

View attachment 64454
Finished radio ready to use.

NB switch rewired for 5KHz dropper
ANL switch rewired for +10KHz shifter
PA switch rewired for Hi band (27.415-27.855)
Clarifier unlocked and extended to +/- 2.5Khz

Apart from the above, radio is standard...

Loz!

Probably a bit above what I can do but where do I get the stuff to do this?

 

[hpssb]

Controller was an Arduino, available on amazon or ebay, synth came from QRP labs.

The 27MHz crystal in the kit would have interfered with channel 4 and also was not quite stable enough for SSB, so it was removed and a 25MHz TCXO (also from QRP labs) was fitted in its place. No interference and no drift after that was added.

I got a tech to do mine. You'll need Adruino coding skills as well as good radio circuitry knowledge to fit it.

 

[Staybolt]

That's too far above my head, sorry. I'll just look for a vfo. I found a crystal to get me to ch 36 to 40.

 

[sunbulls]

A 23.730Mhz crystal is ideal for those that can find one, but it skips 39. Ken has a 23.740Mhz crystal that will give you 37,38,39, but skips 36 and 40 plus the last channel is 27.415Mhz.

 

[Staybolt]

A 23.730Mhz crystal is ideal for those that can find one, but it skips 39. Ken has a 23.740Mhz crystal that will give you 37,38,39, but skips 36 and 40 plus the last channel is 27.415Mhz.

The crystal I used covers 36 to 40 but skips 39. I also had to add a choke and a small vr pot to get it dialed in. Now for some reason I lost my lsb function...