Kenwood TS440S: No QRP...

[Singularity35]

My little radio didn't seem to be 100% duty cycle and got uncomfortably hot during long ragchew sessions. This made me decide(seems like a good excuse too...) to get something that would stand up to long QSO's in spite of the heat here in DU land. It had to be an older rig so it wouldn't cost too much. I finally ended up getting my grubby hands on a TS440S in reasonably good condition(I only had 4 models in the list that I would consider).

We have a local 40 meter net in mornings and evenings and I like to check in doing QRP. Besides QRP stations being first to be called, I also like the idea of getting heard over a few hundred kilometers with just 5 watts. I used to do that on my FT857D.

My problem is that my TS440 doesn't do QRP. I saw a mod on the interwebz that say that I can do QRP if I cut this certain diode giving me control over output using the carrier knob.

Is doing this mod unwise? Thanks in advance.

 

[DainBramage]

cutting D-49 will do what you want.

it is one of MANY 440 mods that are pretty standard.

http://www.radiomods.co.nz/kenwood/kenwoodts440.html

 

[Singularity35]

cutting D-49 will do what you want.

it is one of MANY 440 mods that are pretty standard.

http://www.radiomods.co.nz/kenwood/kenwoodts440.html

Thanks! I have the text of that document saved already. I'm happy to know that those mods are ok to do.

 

[DainBramage]

you really might want to look at the FAN mod too

 

[Singularity35]

you really might want to look at the FAN mod too

Thanks. I should try finding a spare fan too. I do have a small electric fan pointed at the heat sink. With it on, the heat sink barely feels warm after long QSO's. Maybe that'll do in the meantime.

 

[2RT307]

Just curious what your buds on 40 have to say about your new rig. How's the Shure working for you?

73,
Brett

 

[wavrider]

I just put an external fan,
( looks same as the one in your picture) blowing the air on the back of the TS440 and I never have any issues with the rig getting hot, a lot easier than doing the fan mod.

 

[Singularity35]

Just curious what your buds on 40 have to say about your new rig. How's the Shure working for you?

73,
Brett

It seems that everybody on the ragchew channel either has an audio chain or modded mikes. Nobody sounds like themselves.

I'm just going to get an old mike an have it modded with an electret element and a pre amp. I'm keeping the Shure stock.

I just put an external fan,
( looks same as the one in your picture) blowing the air on the back of the TS440 and I never have any issues with the rig getting hot, a lot easier than doing the fan mod.

Thanks, I often have long QSO's and the fan, even on low speed, keeps the rig cool. Barely warm to the touch after my long winded conversations.

 

[Singularity35]

BTW, what's a good(meaning cheap) way to monitor my own audio?

 

[dave457]

a simple rf demodulator,plenty of plans on the net, easy to make

 

[543_Dallas]

a simple rf demodulator,plenty of plans on the net, easy to make

They work great but only for AM.

 

[Singularity35]

a simple rf demodulator,plenty of plans on the net, easy to make

They work great but only for AM.

So what do I do for SSB?

 

[543_Dallas]

So what do I do for SSB?

I just use a second radio and some ear buds. I don't know of a better way for SSB or FM.

 

[Singularity35]

I just use a second radio and some ear buds. I don't know of a better way for SSB or FM.

Thanks, maybe someone has a suggestion that will fit my needs.

 

[2RT307]

I typically do as 543 suggested. Since that's not practical for you... not sure if there is a monitor mod for the 440 or not. Might be worth looking into. Or, if you have a computer with some oomph, look into a SDR. Soft66 is about the cheapest I have found with an upconverter. http://zao.jp/radio/soft66rtl/ HDSDR software is free.

73,
Brett