It has good Tx, but on a crowded channel (I'm in Detroit) the receive is unbearable. Attack of the Birdies!!! I still contend that single conversion just sucks for AM, period.
Hi Tramdr,
You are quite knowledgeable . Judging by your many U-tube video's I stumbled across. Also numerous posts.
Can you part with a copy of the Service Manual? I have a good chunk of it.
Unfortunately the person who sent it to me had a computer crash. So missing parts.
In my opinion. The ARF 2001 is aimed at SSB. Single then is not an issue. Bear in mind the AMSIL circuit.
Do not know much about Detroit. Except that it is in dire straights. 45 minute to 1 hour Police response
time to Felony's in progress. The last Mayor doing hard time. Yup it is annoying when the skip is rolling
in strong here in my part of the corn fields of Nebraska. I will be having a conversation on 19. Then some
Bozo on 21 running a 22 Pill shouting how loud he is blasts through my ARF 2001 Mobile. I remember
one CB personality. Master Blaster from Detroit Michigan ? Apparently no one told him that his Cobra 29
with supposedly Ass-Symmetrical modulation is transmitting across the known frequency spectrum !
600 Watts on 22. The rest every where else ! LOL Could have hooked up my 100 mhz hand me down spectrum analyzer to the antenna.
It would have lit up like a christmas tree when Master Blaster was doing his thing from Detroit.
Seriously.
The transmit is awesome stock. Flip the switch and the sidebands of the audio rock on AM.
Master Blaster ; If he used the ARF instead of his Tech Hacked Cobra 29 would at least put the 1200 Watts
RMS unto channel 22. Garbage in. Garbage out.
The quality of the components. The tolerance specified by the design engineer and his/her goals.
The ARF 2001 clearly has Hi-Fi receive audio as the original designers goal. My opinion.
Manufacturing cost is another factor.
Now. I'm assuming that the 4 pole Crystal filters in series within the ARF 2001 IF chain are 6KHZ wide at
its center frequency. Hence Hi-Fi receive audio. Crystals degrade over time. What is it. 40+ years since
our radios were born ?
Recently spoke with an Engineer now retired in New Mexico. He was not aware of a "Service Manual".
Shoosh. He was involved in the design. Could have asked questions ?
Back to the 4 poles. Its all about cut off and crystal skirt. Ahh not the skirts of women reader.
Noticed a bunch of 2n3904 on the schematic. On my research to recreate and improve the design of CBC
10.695 filter kits. No longer available. Came across a modern sub for 2n3904 drop in replacement. BC
449 or was it 448 ? Lower noise. Higher gain. Or was it BC558? To0 lazy to look up my notes.
The gist of my thesis post and reply.
Replace the four poles in series with 6 poles. 2.4 khz wide. New with sharper skirts. Hopefully its a 455Khz
in the If somewhere. If so. Then a triple with the new Murata 455Khz crystal filters. Sharper narrower
skirts than their originals.
Its all about the Bandpass filtering. Depending on condition. 600 to 1000 + radio. Might be worth the effort.
Lets face it. The receive is a bit noisy. Need a magnifying glass to read this
schematic. Lazy and tired. Have to work in a few hours. Hmm maybe tonight. Have to rebuild an old
school D104 for a friend. Might just try it out first on the ARF 2001. Two transistor variable Compressor
& 1
transistor Mic. amp at the base. In the head; a Shure Lo Z ceramic element.
Maybe one of the best could be made better?
Tramdr. You are a Tinkerer. Don't complain. Do something about it !
ARF 2001 Mobile Link.
I did not come in for an SWR check. It was a social visit. Looking to see what new
snake oil products were on sale.
Anyway he was Kind . Gave me some ept ranger carcasses for free. Was
able to fix one Galaxy radio with the parts.
https://www.facebook.com/pages/Pitbulls-CB-Repair-Shop/236853706487570