Topics

Compliance Summary - other radios

Bill Cromwell <wrcromwell@...>
 

Hi,

I have some other solid state gear and the filtering is more serious. My latest purchase (used) is a Hendricks PFR-3 and with only three bands it contains as many of those funny little donuts than the uBitx. They are also well placed. My old Atlas has a complete set of low pass filters on the output AND the interstage filters. It resembles a box of donuts from a real donut shop. I have a Ten Tec receiver that covers from 300 kHz to 30 MHz and has seven switched filters in just the front end and some more in the synthesizer section.

I also have a Dentron 80 meter rig rated for 12 watts with absolutely no filter after the final!! I have it sitting on the shelf just because I cared to remove the cover and look. No filter shows up on the schematic. Can't be. But it is. Now that uBitx has my attention I will probably roll a set of filters for that Dentron too.

UBitx is fixable.

73,

Bill KU8H

On 08/11/2018 12:32 AM, Dennis Yancey wrote:
I wonder what other kits and factory radios actually look like in
comparison on exactly the same teapots. For instance, I was listening to
a gentleman who is an extra class talking on 40 meters last night. He
USA using a high dollar radio, so he said, a high dollar amplifier and
he was 3 states away from me. His emissions were covering 8 kHz on
either side of the frequency he was using. That is just one of many. .
--
72 and God bless
KD4EPG
_._,_._,_
--
bark less - wag more

Timothy Fidler
 

arghgh rew WBand SSB that might be one of those MPa'70 home built  amps as in 20 dollars on ebay and no filter set  or perhaps an RM Italia amp with no filter (some yes,  some no plenty of hoods off photos on the internet to show the awful truth)   and run right at the stops in terms of drive. .. and the FCC does nix even though they are factory built amps and should have compliance tests before entry.
 

Timothy E. Fidler : Engineer BE Mech(1) Auckland , NDT specialist AINDT UT /RT3 , MT2 
Telephone Whangarei   022  691 8405
e: Engstr@...



----- Original Message -----
From:
BITX20@groups.io

To:
<BITX20@groups.io>
Cc:

Sent:
Sat, 11 Aug 2018 06:03:33 -0400
Subject:
Re: [BITX20] Compliance Summary - other radios


Hi,

I have some other solid state gear and the filtering is more serious. My
latest purchase (used) is a Hendricks PFR-3 and with only three bands it
contains as many of those funny little donuts than the uBitx. They are
also well placed. My old Atlas has a complete set of low pass filters on
the output AND the interstage filters. It resembles a box of donuts from
a real donut shop. I have a Ten Tec receiver that covers from 300 kHz to
30 MHz and has seven switched filters in just the front end and some
more in the synthesizer section.

I also have a Dentron 80 meter rig rated for 12 watts with absolutely no
filter after the final!! I have it sitting on the shelf just because I
cared to remove the cover and look. No filter shows up on the schematic.
Can't be. But it is. Now that uBitx has my attention I will probably
roll a set of filters for that Dentron too.

UBitx is fixable.

73,

Bill KU8H

On 08/11/2018 12:32 AM, Dennis Yancey wrote:
> I wonder what other kits and factory radios actually look like in
> comparison on exactly the same teapots. For instance, I was listening to
> a gentleman who is an extra class talking on 40 meters last night. He
> USA using a high dollar radio, so he said, a high dollar amplifier and
> he was 3 states away from me. His emissions were covering 8 kHz on
> either side of the frequency he was using. That is just one of many. .
> --
> 72 and God bless
> KD4EPG
> _._,_._,_

--
bark less - wag more



Bill Cromwell <wrcromwell@...>
 

Hi,

Apparently Dentron never got that radio into full production. I have only ever seen mine for 80 meters and another I exchanged info with another ham. His was for 20 meters. We had the same 5 MHz VFO and 9 MHz xtal filter. I will finish building a radio on it.

73,

Bill KU8H

On 08/11/2018 06:41 AM, Timothy Fidler wrote:
arghgh rew WBand SSB that might be one of those MPa'70 home built amps
as in 20 dollars on ebay and no filter set or perhaps an RM Italia amp
with no filter (some yes, some no plenty of hoods off photos on the
internet to show the awful truth) and run right at the stops in terms
of drive. .. and the FCC does nix even though they are factory built
amps and should have compliance tests before entry.


Timothy E. Fidler : Engineer BE Mech(1) Auckland , NDT specialist AINDT
UT /RT3 , MT2
Telephone Whangarei 022 691 8405
e: Engstr@...



----- Original Message -----
From:
BITX20@groups.io

To:
<BITX20@groups.io>
Cc:

Sent:
Sat, 11 Aug 2018 06:03:33 -0400
Subject:
Re: [BITX20] Compliance Summary - other radios


Hi,

I have some other solid state gear and the filtering is more
serious. My
latest purchase (used) is a Hendricks PFR-3 and with only three
bands it
contains as many of those funny little donuts than the uBitx. They are
also well placed. My old Atlas has a complete set of low pass
filters on
the output AND the interstage filters. It resembles a box of donuts
from
a real donut shop. I have a Ten Tec receiver that covers from 300
kHz to
30 MHz and has seven switched filters in just the front end and some
more in the synthesizer section.

I also have a Dentron 80 meter rig rated for 12 watts with
absolutely no
filter after the final!! I have it sitting on the shelf just because I
cared to remove the cover and look. No filter shows up on the
schematic.
Can't be. But it is. Now that uBitx has my attention I will probably
roll a set of filters for that Dentron too.

UBitx is fixable.

73,

Bill KU8H

On 08/11/2018 12:32 AM, Dennis Yancey wrote:
> I wonder what other kits and factory radios actually look like in
> comparison on exactly the same teapots. For instance, I was
listening to
> a gentleman who is an extra class talking on 40 meters last night. He
> USA using a high dollar radio, so he said, a high dollar amplifier and
> he was 3 states away from me. His emissions were covering 8 kHz on
> either side of the frequency he was using. That is just one of many. .
> --
> 72 and God bless
> KD4EPG
>
--
bark less - wag more

iz oos
 

Tim, I am not absolutely sure but regarding the RM-Italy without lowpass filters I think they are not imported in the USA. If you download the manuals from their site they state the user must provide a low pass filter and they sell a 30mhz low pass filter for 10 meters. If you use it without a proper filter that is not allowed. They warn the buyer at least. There are other RM Italy models that have low pass filters for all the HF bands. They cost more of course and I think these models are exported to the US.


Il 11/ago/2018 17:52, "Timothy Fidler" <engstr@...> ha scritto:
arghgh rew WBand SSB that might be one of those MPa'70 home built  amps as in 20 dollars on ebay and no filter set  or perhaps an RM Italia amp with no filter (some yes,  some no plenty of hoods off photos on the internet to show the awful truth)   and run right at the stops in terms of drive. .. and the FCC does nix even though they are factory built amps and should have compliance tests before entry.
 

Timothy E. Fidler : Engineer BE Mech(1) Auckland , NDT specialist AINDT UT /RT3 , MT2 
Telephone Whangarei   022  691 8405
e: Engstr@...



----- Original Message -----

To:
<BITX20@groups.io>
Cc:

Sent:
Sat, 11 Aug 2018 06:03:33 -0400
Subject:
Re: [BITX20] Compliance Summary - other radios


Hi,

I have some other solid state gear and the filtering is more serious. My
latest purchase (used) is a Hendricks PFR-3 and with only three bands it
contains as many of those funny little donuts than the uBitx. They are
also well placed. My old Atlas has a complete set of low pass filters on
the output AND the interstage filters. It resembles a box of donuts from
a real donut shop. I have a Ten Tec receiver that covers from 300 kHz to
30 MHz and has seven switched filters in just the front end and some
more in the synthesizer section.

I also have a Dentron 80 meter rig rated for 12 watts with absolutely no
filter after the final!! I have it sitting on the shelf just because I
cared to remove the cover and look. No filter shows up on the schematic.
Can't be. But it is. Now that uBitx has my attention I will probably
roll a set of filters for that Dentron too.

UBitx is fixable.

73,

Bill KU8H

On 08/11/2018 12:32 AM, Dennis Yancey wrote:
> I wonder what other kits and factory radios actually look like in
> comparison on exactly the same teapots. For instance, I was listening to
> a gentleman who is an extra class talking on 40 meters last night. He
> USA using a high dollar radio, so he said, a high dollar amplifier and
> he was 3 states away from me. His emissions were covering 8 kHz on
> either side of the frequency he was using. That is just one of many. .
> --
> 72 and God bless
> KD4EPG

ajparent1/KB1GMX
 

When I tested the ubitx it triggered exactly the same question.  

How are the other radios?

The list includes:
FT817, Argonaut 505, Triton m540, Eagle, KNQ7A, 20 Slopbucket, Kitsandparts 1W (cw only),
and homebrew SSB monoband radios for 40,20,15,10.  For ancient to compare to I
warmed up the HW101, Siltronix 1110C, and Tempo-one as an excuse to make sure
they were ok and put a little time on them.  

The verdict was all passed with margin.  Some the margin was more than 20db. 
For example my 1977 (manufacture date) Tentec Triton M430 the specs said not 
less than -60dbc and it was better than spec 43 years later for everything.  The 
modern OK mines about 12 years old) FT817 was spec or better.  

The poorest exceed spec was the 20M Small wonder labs White Mountain
SSB as harmonics were-43dbc (at max power 3W) and the peak was 
second harmonic with the rest better and carrier was -46dbc.  Not 
bad for a 20 year old design and in use for the last 14 years.

A recent build is the 20M slopbucket a KD1JV design.  Harmonics better 
than -45 for second and better for higher. Carrier was -49db.

For many simple radios the second harmonic is to be watched because 
of the single ended output as its also harder to filter.  the WM20, Slopbucket,
and KNQ7A and nearly all of mine fall into that category.  They pass.

Also I can take any radio and push it to get truly horrific results.  Can't
blame the radio for that.

The tube rigs were interesting as once dialed up for the band it was good
but over driven or tuned up wrong the second harmonic could climb out of
accept range.  Considering the output of both of those were only single
section pi networks for the outputs one would expect worse.  OF note
was that spurs other than harmonics were not at all strong most being
better than -55dbc.  This is attributed to much filtering (tuned preselection)
in the lower level stages and the driver as well.  Considering the
Siltronix 1011C  goes back to the days was 11M was a ham band
it was fine on 10M and fun.

Filtering in the early stages does help and all do it that way with low
pass filters for harmonic clean up due to the amplifiers used.  AS a result
spurs were non existent or very low.

One odd item as a response...  I have a siltronics 100W "cb" amp.
With mods (bias circuit added) for class AB1 (1a standing current) rather
than class B (zero bias) the push pull amps is close to that of Motorola AN63
with MRF454s.  So I tested it without the nominal low pass filters used with
it.  The drive was FT817 at 5W so the output was about 63W for 80 and 40
(works well higher but not tested for this) and harmonics were -38DBC for
second harmonic and -33dbc for the third harmonic the rest were lower.  Of
course it didn't pass but as to calling it filthy, not so much.    With external
filters normally used in place in the results were easily 15db (for second)
and 23db (for the third) which is better than required.  With harmonic
suppression in the  mid -50s, 53dbc and 56dbc for both bands case closed.

The filters, a set of filters built almost like those for the ubitx using the
same values with differences, bigger toroids, higher voltage caps and used a 
dual section 4 position switch. Covers 80-60, 40, 20-17, 21-29mhz.
I built it last year so I never thought to try it with ubitx but based on 
this it would clean it up.



Allison

ajparent1/KB1GMX
 

Iz ooz,

The only RM Italy amps I've seen were the ones with selectable filters.
They worked well and were clean.  The owners liked them.  I thought
them a bit pricey.

Allison

ajparent1/KB1GMX
 

Too repeat.... and not have to answer the private emails...

RE: external amp filter:

>>a set of filters built almost like those for the ubitx using the
same values with differences, bigger toroids, higher voltage caps and used a 
dual section 4 position switch. Covers 80-60, 40, 20-17, 21-29mhz.
I built it last year so I never thought to try it with ubitx but based on 
this it would clean it up.<<

That means:

The value for the capacitors are the same as are the values for the
inductors and capacitors as used in ubitx.  Just grab a copy of the
schematic and read them off.  Its not a secret.

I didn't use relays, I used a 2 pole four position switch. this was
build a year pre ubitx.

I did use larger toroids and higher voltage caps to allow 100W.  

Or Goodle/Bing/DUCKDUCK go:  Building low pass filters.

Allison

iz oos
 

Interesting survey, so, generally speaking, except for the current uBitx, both the Wright brothers and NASA are complaint independently of the cost (!) and the age (!) of the flying object...


Il 11/ago/2018 19:02, "ajparent1/KB1GMX" <kb1gmx@...> ha scritto:
When I tested the ubitx it triggered exactly the same question.  

How are the other radios?

The list includes:
FT817, Argonaut 505, Triton m540, Eagle, KNQ7A, 20 Slopbucket, Kitsandparts 1W (cw only),
and homebrew SSB monoband radios for 40,20,15,10.  For ancient to compare to I
warmed up the HW101, Siltronix 1110C, and Tempo-one as an excuse to make sure
they were ok and put a little time on them.  

The verdict was all passed with margin.  Some the margin was more than 20db. 
For example my 1977 (manufacture date) Tentec Triton M430 the specs said not 
less than -60dbc and it was better than spec 43 years later for everything.  The 
modern OK mines about 12 years old) FT817 was spec or better.  

The poorest exceed spec was the 20M Small wonder labs White Mountain
SSB as harmonics were-43dbc (at max power 3W) and the peak was 
second harmonic with the rest better and carrier was -46dbc.  Not 
bad for a 20 year old design and in use for the last 14 years.

A recent build is the 20M slopbucket a KD1JV design.  Harmonics better 
than -45 for second and better for higher. Carrier was -49db.

For many simple radios the second harmonic is to be watched because 
of the single ended output as its also harder to filter.  the WM20, Slopbucket,
and KNQ7A and nearly all of mine fall into that category.  They pass.

Also I can take any radio and push it to get truly horrific results.  Can't
blame the radio for that.

The tube rigs were interesting as once dialed up for the band it was good
but over driven or tuned up wrong the second harmonic could climb out of
accept range.  Considering the output of both of those were only single
section pi networks for the outputs one would expect worse.  OF note
was that spurs other than harmonics were not at all strong most being
better than -55dbc.  This is attributed to much filtering (tuned preselection)
in the lower level stages and the driver as well.  Considering the
Siltronix 1011C  goes back to the days was 11M was a ham band
it was fine on 10M and fun.

Filtering in the early stages does help and all do it that way with low
pass filters for harmonic clean up due to the amplifiers used.  AS a result
spurs were non existent or very low.

One odd item as a response...  I have a siltronics 100W "cb" amp.
With mods (bias circuit added) for class AB1 (1a standing current) rather
than class B (zero bias) the push pull amps is close to that of Motorola AN63
with MRF454s.  So I tested it without the nominal low pass filters used with
it.  The drive was FT817 at 5W so the output was about 63W for 80 and 40
(works well higher but not tested for this) and harmonics were -38DBC for
second harmonic and -33dbc for the third harmonic the rest were lower.  Of
course it didn't pass but as to calling it filthy, not so much.    With external
filters normally used in place in the results were easily 15db (for second)
and 23db (for the third) which is better than required.  With harmonic
suppression in the  mid -50s, 53dbc and 56dbc for both bands case closed.

The filters, a set of filters built almost like those for the ubitx using the
same values with differences, bigger toroids, higher voltage caps and used a 
dual section 4 position switch. Covers 80-60, 40, 20-17, 21-29mhz.
I built it last year so I never thought to try it with ubitx but based on 
this it would clean it up.



Allison

iz oos
 

Yes, shipping, duties and other margins will rise the price quite a lot. It's the same in Europe for reasonably priced US amps like Ameritron that nearly cost as much as a Acom. So I Iook forward for the uAMP...!!!


Il 11/ago/2018 19:05, "ajparent1/KB1GMX" <kb1gmx@...> ha scritto:
Iz ooz,

The only RM Italy amps I've seen were the ones with selectable filters.
They worked well and were clean.  The owners liked them.  I thought
them a bit pricey.

Allison


Skip Davis
 

Bill I also have one of the Dentron radios for 20 meters, plus I have a spare board with the filter and I think also the RX frontend board in a box. One day I’ll get it out of the box and back on the air.

Skip Davis, NC9O

On Aug 11, 2018, at 12:02, Bill Cromwell <wrcromwell@...> wrote:

Hi,

Apparently Dentron never got that radio into full production. I have only ever seen mine for 80 meters and another I exchanged info with another ham. His was for 20 meters. We had the same 5 MHz VFO and 9 MHz xtal filter. I will finish building a radio on it.

73,

Bill KU8H

On 08/11/2018 06:41 AM, Timothy Fidler wrote:
arghgh rew WBand SSB that might be one of those MPa'70 home built amps
as in 20 dollars on ebay and no filter set or perhaps an RM Italia amp
with no filter (some yes, some no plenty of hoods off photos on the
internet to show the awful truth) and run right at the stops in terms
of drive. .. and the FCC does nix even though they are factory built
amps and should have compliance tests before entry.


Timothy E. Fidler : Engineer BE Mech(1) Auckland , NDT specialist AINDT
UT /RT3 , MT2
Telephone Whangarei 022 691 8405
e: Engstr@...



----- Original Message -----
From:
BITX20@groups.io

To:
<BITX20@groups.io>
Cc:

Sent:
Sat, 11 Aug 2018 06:03:33 -0400
Subject:
Re: [BITX20] Compliance Summary - other radios


Hi,

I have some other solid state gear and the filtering is more
serious. My
latest purchase (used) is a Hendricks PFR-3 and with only three
bands it
contains as many of those funny little donuts than the uBitx. They are
also well placed. My old Atlas has a complete set of low pass
filters on
the output AND the interstage filters. It resembles a box of donuts
from
a real donut shop. I have a Ten Tec receiver that covers from 300
kHz to
30 MHz and has seven switched filters in just the front end and some
more in the synthesizer section.

I also have a Dentron 80 meter rig rated for 12 watts with
absolutely no
filter after the final!! I have it sitting on the shelf just because I
cared to remove the cover and look. No filter shows up on the
schematic.
Can't be. But it is. Now that uBitx has my attention I will probably
roll a set of filters for that Dentron too.

UBitx is fixable.

73,

Bill KU8H

On 08/11/2018 12:32 AM, Dennis Yancey wrote:
> I wonder what other kits and factory radios actually look like in
> comparison on exactly the same teapots. For instance, I was
listening to
> a gentleman who is an extra class talking on 40 meters last night. He
> USA using a high dollar radio, so he said, a high dollar amplifier and
> he was 3 states away from me. His emissions were covering 8 kHz on
> either side of the frequency he was using. That is just one of many. .
> --
> 72 and God bless
> KD4EPG
>
--
bark less - wag more


Sajid Rahum
 

Hi Allison, i did get the prebuilt band pass filter from ebay.  Wondering if you have any suggestions to mod the KL-203 as well as how to mod it to be more sensistive to lower power e.g. from softrock <1w; I am able to trigger AM but not via SSB.

Curt
 

Bill

On the Dentron, see if it uses a narrowband matching circuit, although that would also result in output power varying appreciably across the band. If you have a nearby RBN listener as I do, it may let you preceive the 40m harmonic level. My local RBN showed a simultaneous 14 MHz output when I used my hw16 on 15m, that I successfully adjusted. That's a sure problem feeding my triband yagi.

The nice kit being sold by N8DAH nicely addresses ubitx harmonics, last I heard in every tested ubitx by our club. It does not cure ssb upper band spurious on 15, 12 and 10m. (I am skeptical whether arrl lab knew to look for these in v5 testing).

Those single and few band rigs can incorporate narrower filters, making compliance easier.

Curt

iz oos
 

The KL203 senses the RF and less than 1w average power is needed. That is why it works as is with a softrock in AM FM and likely in CW. In SSB the average power is far less as in most transceivers unless a mic compressor is used. A simple mod I believe is simply to increase a little bit the picking of RF at the RX input of the KL203. The KL203 uses a 500V 8.2pf at C1. I would add another 8.2pf in parallel at C1. If you use the KL203 with 1w you may use also a non 500V cap, any will work.


Il 12/set/2019 20:14, "Sajid Rahum via Groups.Io" <zs735=yahoo.com@groups.io> ha scritto:
Hi Allison, i did get the prebuilt band pass filter from ebay.  Wondering if you have any suggestions to mod the KL-203 as well as how to mod it to be more sensistive to lower power e.g. from softrock <1w; I am able to trigger AM but not via SSB.

Ted
 

Not a bad deal (as of date of this message) considering those "kits" on eBay that self-destruct upon contact with electricity:

  https://www.newegg.com/p/0TF-0002-00002