HTX-10 freq expansion with resistor?

[Pez]

Color me skeptical. Is the firmware inside it the same? That's what really counts. If the chips each have identical markings, that would be a good sign.

73

Regardless of the marking on the chip, the FIRMWARE IS DIFFERENT ON A HTX-10. It does NOT include the firmware required for anything except 28.000 to 29.699.
Anyone who tells you otherwise has no idea what they are talking about and does not understand how these radios work, OR the significant differences between all of these rigs that "look" the same on the outside.

Unless the PLL chip is changed for one with a different and complete firmware (from a Dragon, Magnum, Titan, Albrecht, etc), or a crystal is swapped out to move the master reference, then the HTX-10 is not able to be modified. And even then, it's literally not worth the trouble. It's not a small job, for a less than perfect result.

It amazes me how long this silly rumor has been in circulation. Decades now, and not one single HTX-10 has appeared outside of the 10m band in all that time (with some simple "resistor mod", or similar). And that is for good reason.

73

 

[towerdog]

It's hidden under the PLL chip

 

[Pez]

It's hidden under the PLL chip

It never ends. Oh well, I tried.

73

 

[towerdog]

It never ends. Oh well, I tried.

73

11 year old thread. I don't like the word can't, where there is a will there is a way, but there should also be a market for it.

 

[357]

so htx10 is not modifiable with a 10 ohm and the button press?

 

[SuperLid]

so htx10 is not modifiable with a 10 ohm and the button press?

NO!!!!

 

[SuperLid]

11 year old thread. I don't like the word can't, where there is a will there is a way, but there should also be a market for it.

Yeah the mod is buy a Radioddity QT-80.

 

[SuperLid]

It's hidden under the PLL chip

I'm selling a bridge, It's in Brooklyn. Interested?

 

[AudioShockwav]

They really did a good job of locking the door on out of band operations , never seen this model outside of 10 meters even though there were export clones that looked identical.
Even the HTX-100 was not worth the effort as they only had USB and CW, but they did make a great 10 meter rig if left alone.

73
Jeff

 

[SuperLid]

They really did a good job of locking the door on out of band operations , never seen this model outside of 10 meters even though there were export clones that looked identical.
Even the HTX-100 was not worth the effort as they only had USB and CW, but they did make a great 10 meter rig if left alone.

73
Jeff

I did the out of band mod to my HTX-100 decades ago, which I am very fond of. I had planned in my head, to add LSB, using one of the front panel switches. It is still in my head, like the gazillion other projects. Maybe some day .

 

[nomadradio]

I had planned in my head, to add LSB,

With all due respect, that's where this mod will remain. A casual look at the schematic reveals parts that were left out of this radio you would need for LSB. I don't have a pic of the circuit board layout. If there are empty holes where those parts would have gone in a separate model radio, that would simplify things. You would only need to come up with parts for the carrier-oscillator circuit and a switch. But bear in mind that the CPU performs the offset shift. The radio's local oscillator is what sets the operating frequency. To change sideband modes you change the frequency of the carrier crystal inside. But now your displayed frequency won't be right. The PLL shifts its local oscillator frequency the opposite amount to keep the frequency displayed correct. Only knows how to do that for USB and CW. No way that feature is hiding in the CPU's firmware. Best case if you install the third offset frequency to the carrier oscillator crystal is that the displayed frequency will be wrong by around 3 kHz in LSB mode.

Never have heard of anyone trying this, but if you do, it might be for the very first time.

73

 

[KneeBiter]

I did this LSB mod years ago. Still have the radio. It works awesome. The offset on the display is off on LSB but once you understand that and know where you are it doesn't matter. The radio actually has a great receiver and good audio. I used an Astatic 575 that I powered from the mic plug. Used one of the extra wires in the cord.

 

[SuperLid]

With all due respect, that's where this mod will remain. A casual look at the schematic reveals parts that were left out of this radio you would need for LSB. I don't have a pic of the circuit board layout. If there are empty holes where those parts would have gone in a separate model radio, that would simplify things. You would only need to come up with parts for the carrier-oscillator circuit and a switch. But bear in mind that the CPU performs the offset shift. The radio's local oscillator is what sets the operating frequency. To change sideband modes you change the frequency of the carrier crystal inside. But now your displayed frequency won't be right. The PLL shifts its local oscillator frequency the opposite amount to keep the frequency displayed correct. Only knows how to do that for USB and CW. No way that feature is hiding in the CPU's firmware. Best case if you install the third offset frequency to the carrier oscillator crystal is that the displayed frequency will be wrong by around 3 kHz in LSB mode.

Never have heard of anyone trying this, but if you do, it might be for the very first time.

73

It has been done by many before me, just not the way I have in mind, which may or may not work. If my thinking goes sideways, I could do whatever everyone else did, which sacrifices CW for LSB, *if* I ever get around to it. The display will read high, but I don't care.

 

[Crawdad]

Who would one talk to on 10m LSB??

 

[SuperLid]

Who would one talk to on 10m LSB??

It is referencing 11m, with HTX-100.