Homebrew SI4732 HF Receiver?

[TailGator911]

This little receiver advertises for under $100 on eBay. The listing is a little confusing and I wonder if this is a working radio out of the box or a kit you build. Anybody have any experience with this receiver? Who actually makes it? Any info much appreciated. As always, looking for a new toy

 

[VA3TFC]

I have watched videos on YouTube about this receiver. Yes some come fully assembled and ready to use while I believe others come in a kit form.
I am not sure if I am sold on this receiver yet since it's one of those ones that can be connected to a computer to change some of it's functions and that is certainly not something I want or need. I don't have a computer new enough for this type of technology. Also I have seen videos and read reports that many of these radios come with problems that...sure can be fixed if you hook it up to a computer....
No thanks.

 

[dlwtrunked]

This little receiver advertises for under $100 on eBay. The listing is a little confusing and I wonder if this is a working radio out of the box or a kit you build. Anybody have any experience with this receiver? Who actually makes it? Any info much appreciated. As always, looking for a new toy

I have one (the assembled black model) sitting right next to me. Nice looking and well physically constructed. On FM broadcast band, sounds nice and really nice with headphones (it is AM/HF plus FM broadcast band). On HF, forget using the whip antenna, it is not all that sensitive and suffers from generating its own noise. Not useful on HF except for very strong signals. If it were, it would be a game changer.

 

[dlwtrunked]

I have one (the assembled black model) sitting right next to me. Nice looking and well physically constructed. On FM broadcast band, sounds nice and really nice with headphones (it is AM/HF plus FM broadcast band). On HF, forget using the whip antenna, it is not all that sensitive and suffers from generating its own noise. Not useful on HF except for very strong signals. If it were, it would be a game changer.

In what I just posted, I should add "even with an external antenna, only useful for strong signals".

 

[TailGator911]

Heck, I just might pull the trigger for the am/fm broadcast bands and because it looks cooler than the old fuddy-duddy that I have haha. I like pulling up local am/fm news stations whenever we are on severe weather warnings and I listen to them with the SkyWarn reports and NOAA. The SI4732 looks capable enough from what I am reading here and elsewhere and the price is right. It also just looks like it belongs on my desk.

 

[TailGator911]

It's going to be a challenge to get this little radio fully assembled and operational and not from China. I don't do Chinese anymore. Well, okay, I do their food quite often, but not eBay or Etsy or Amazon sellers. They know this, so some of them cleverly disguise the fact that they are located overseas. I recently ordered something from Amazon and didn't realize it was from Hong Kong when their profile said they were in San Jose, CA. Took almost 2 months to get to me after I complained to Amazon who refunded my money. When I called Amazon to send it back they said just keep it and fuggitaboutit. Whaddya gonna do?

 

[VA3TFC]

I have not had bad luck with the Hong Kong or Chinese sellers. I normally buy from longtime eBay sellers with a 99-100% rating. Yes a couple of items I have bought took 6-8 weeks to arrive but one seller I have recently bought from shipped the item from China and it was delivered 10 days later. That was with free shipping.

As for the si4732 receiver when I first saw it I was interested in it but after seeing how it works on YouTube I decided my money would be better spent elsewhere.

 

[TailGator911]

Yeah I watched a few Utube vids and decided the same thing, not for me. No memories, no scan, and questionable hf coverage. A little too smaller than what I thought. I'll keep searching for a good CommRadio CR-1 for that little spot on my desk. That is proving to be a challenging search.

 

[KEWB-N1EXA]

This little receiver advertises for under $100 on eBay. The listing is a little confusing and I wonder if this is a working radio out of the box or a kit you build. Anybody have any experience with this receiver? Who actually makes it? Any info much appreciated. As always, looking for a new toy

I have the SI 4732...Took 3 weeks form Hong Kong to Arrive ...Paid $56 with free Shipping

It does a good Job on Am and SSB/CW...I use a 30 foot long wire and listen to WRMI Florida in the evening and 40 Meter Code at night.
Have no issuse's with 20 meter during the day,

Its a small SDR receiver that uses Software to run that is internal to the Rig..Takes about 30 seconds to boot up when turned on and Covers
Major sections of the SW band but not Completely 1-30 Mhz

I Also have an R-5000 and no its not going to Match the filtering nor Specrum but the 4732 is a great night table radio.

The battery life is very long...Ive run it for hours without having it die...When your done after a few days just recharge with a Micro USB port.

Pete N1EXA

 

[KEWB-N1EXA]

I have watched videos on YouTube about this receiver. Yes some come fully assembled and ready to use while I believe others come in a kit form.
I am not sure if I am sold on this receiver yet since it's one of those ones that can be connected to a computer to change some of it's functions and that is certainly not something I want or need. I don't have a computer new enough for this type of technology. Also I have seen videos and read reports that many of these radios come with problems that...sure can be fixed if you hook it up to a computer....
No thanks.

I have this radio and you don't need a computer to use it... It has its own internal processor and the firmware is installed...

It works just fine for what it is ... I have it hooked up to a 30 foot wire and if it gets to much signal turn on the AGC or use the Attenuator
function.

Ive seen the You tube video and the guy had no clue on how to use it !

Peter N1EXA

 

[dlwtrunked]

...
Its a small SDR receiver that uses Software to run that is internal to the Rig..Takes about 30 seconds to boot up when turned on and Covers
Major sections of the SW band but not Completely 1-30 Mhz
...

You might want to double check--mine tunes 149 kHz to 30 MHz with no gaps--be sure you fully use the knob to see the range and not in each "band" it returns to where last tuned in that band. As I mentioned,not all that sensitive due to the dynamic range and its own noise. Cute, physically nice, bit not useful as an HF portable m except for very very strong stations..

 

[KEWB-N1EXA]

You might want to double check--mine tunes 149 kHz to 30 MHz with no gaps--be sure you fully use the knob to see the range and not in each "band" it returns to where last tuned in that band. As I mentioned,not all that sensitive due to the dynamic range and its own noise. Cute, physically nice, bit not useful as an HF portable m except for very very strong stations..

Just tried mine and it when low as 153 khz... Im not finding continous coverage but limits to each band selected ...When I get to the top
of each band is then goes to the bottom again... Now this could be totally based on the firmware loaded in.
I agree its no going to compete with a full blown HF Reciever but its not going to be a dead duck either. Just like my Noo Smart SDR that
runs on HDSDR on the laptop...It will never replace a Real radio But it is amazing what they do for what it is.

If you want to be Totally let down buy the MFJ regenerative HF receiver or the ten tec model. I found them both to be Useless for the hobby !

Pete N1EXA

 

[KEWB-N1EXA]

Here is the Firmware data for the unit I have.
I'm sure there is more than 1 version out on the market.
If you upgrade the unit it wont have these specs below.

1) FM, AM (MW and SW) and SSB (LSB and USB);
2) Audio bandwidth filter 0.5, 1, 1.2, 2.2, 3 and 4Khz;
3) 22 commercial and ham radio bands pre configured;
4) BFO Control; and
5) Frequency step switch (1, 5 and 10KHz);
Band band[] = {
{FM_BAND_TYPE, 8400, 10800, 10430, 10},
{LW_BAND_TYPE, 100, 510, 300, 1},
{MW_BAND_TYPE, 520, 1720, 810, 10},
{SW_BAND_TYPE, 1720, 3500, 1900, 1}, // 160 meters
{SW_BAND_TYPE, 3500, 4500, 3700, 1}, // 80 meters
{SW_BAND_TYPE, 4500, 5500, 4850, 5},
{SW_BAND_TYPE, 5500, 6300, 6000, 5},
{SW_BAND_TYPE, 6300, 7800, 7050, 5}, // 40 meters
{SW_BAND_TYPE, 7800, 10000, 9600, 5},
{SW_BAND_TYPE, 10000, 11000, 10100, 1}, // 30 meters
{SW_BAND_TYPE, 11000, 12500, 11940, 5},
{SW_BAND_TYPE, 12500, 13900, 13600, 5},
{SW_BAND_TYPE, 13900, 14500, 14270, 1}, // 20 meters
{SW_BAND_TYPE, 14500, 15900, 15300, 5},
{SW_BAND_TYPE, 15900, 17900, 17600, 5},
{SW_BAND_TYPE, 17900, 18300, 18100, 1}, // 17 meters
{SW_BAND_TYPE, 18300, 21900, 21200, 1}, // 15 mters
{SW_BAND_TYPE, 21900, 26200, 24940, 1}, // 12 meters
{SW_BAND_TYPE, 26200, 27900, 27500, 1}, // CB band (11 meters)
{SW_BAND_TYPE, 27900, 30000, 28400, 1}}; // 10 meters

 

[dlwtrunked]

Note that the definition of "bands" is purely a manufacture thing. I (and think most others) would preferred the radio have a simple up or down 1 MHz control instead of a manufacturer defined band up and down control.

 

[dlwtrunked]

Just tried mine and it when low as 153 khz... Im not finding continous coverage but limits to each band selected ...When I get to the top
of each band is then goes to the bottom again... Now this could be totally based on the firmware loaded in.
I agree its no going to compete with a full blown HF Reciever but its not going to be a dead duck either. Just like my Noo Smart SDR that
runs on HDSDR on the laptop...It will never replace a Real radio But it is amazing what they do for what it is.

If you want to be Totally let down buy the MFJ regenerative HF receiver or the ten tec model. I found them both to be Useless for the hobby !

Pete N1EXA

But when you get to the top of a band, you are supposed to go up to the next band whose lowest frequency is the highest of the band you had previously. That is the whole idea of "bands"--they cover only a segment of the spectrum. So the receiver has continuous coverage but bands are bands and have only continuous coverage of that band. Regarding MFJ, never bought anything from them since the 1970's and found parts glued with Elmer's glue into place.
(I use my AirSpy HF+ Discovery more often than my R9500 or R8600. An AirSpy HF+ Discovery works unbelievably well and I would call it a real radio performing on par with the other two if not better.)