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KB1IAI
10-25-2007, 04:13 PM
i have a cheap little cb that i would like to convert to ten meters. then i would like to add cw to it.
the idea is to make do, not brand new.
todays society believes in throw it out and buy new.
im an old guy. i like to build stuff.
the cb is a uniden pro510xl, little am job i bought at a tag sale for $5.00.
thanks in advance.

N8YX
10-25-2007, 04:51 PM
Quote[/b] (KB1IAI @ Oct. 25 2007,09:13)]i have a cheap little cb that i would like to convert to ten meters. then i would like to add cw to it.
the idea is to make do, not brand new.
todays society believes in throw it out and buy new.
im an old guy. i like to build stuff.
the cb is a uniden pro510xl, little am job i bought at a tag sale for $5.00.
thanks in advance.
That unit used a ROM-based PLL and is going to require a reference-oscillator crystal change...it's not as simple as changing logic states on one of the PLL chip's programming pins.

Look around for Lou Franklin's books on the subject. Many folks have used his material when converting CB rigs for 10M duty...

WJ5O
10-25-2007, 05:04 PM
from Lou Franklin's "CB PLL Data book"
SM5124A ROM chip..."NOT EASILY MODIFIED"
I admire Your "do it Yourself" attitude...... "Homebrew" is becoming a lost art in Ham Radio......

K8ERV
10-25-2007, 05:05 PM
Since CB is 11 meters, all you have to do is to hack off one meter-- (just trying to be helpful)--

Tom K8ERV Montrose Co.

W8GTF
10-25-2007, 05:06 PM
I've got one of those same exact models. I was basically told I could set it up as a beacon, but that was about it.

I don't mean to discourage you, and if you get detailed instructions. I'd love to see them and try to emulate.

KB1IAI
10-25-2007, 05:20 PM
thanks tom. life is too short to be mad at anyone.
lmao

W9AFB
10-25-2007, 06:18 PM
Some of the older 23 ch radios are much easier to convert. You can find many of those models for under $10 on ebay if you still want to homebrew a radio.

KE4FES
10-25-2007, 08:28 PM
http://www.qrz.com/iB_html/non-cgi/emoticons/tounge.gif SELL OR GIVE IT TO A CB'er. Find another type built on a Uniden board, 40 Channels- AM and SSB.
#Using an occ.. crystal , 10.240 MHZ for it's PROGRAMMING DEVIDER, IC CHIP. Several brand names,
President / Cobra etc. used the same design board. As suggested by others, get Lou Franklins book on that subject. For crystals ; try JANS CRYSTALS [1-800] 526-9825.

Charlie

W2BBQ
10-25-2007, 08:43 PM
If I only still had that Uniden President Adams am/ssb with the digiscan box http://www.qrz.com/iB_html/non-cgi/emoticons/tounge.gif

W5HTW
10-25-2007, 08:55 PM
I'm not familiar with this radio, but many 40 channel AM/SSB radios made very good ten meter radios. I was a Pace dealer in business radio, and often saw Pace SSB CB radios come to my shop for modification. But that is not the only brand. A lot of the late-70s 40 channel rigs required nothing more than changing the reference crystal and doing a bit of re-tweaking. Some, like Hy-Gain, were a bit harder. Others, like Teaberry, were extremely easy, almost as easy as just plugging in a different crystal.

I never converted any to CW operation, though. It should be easy enough to do. Simply defeat the modulation scheme on AM (removing any audio) and find a way to key the rig with an external keyer. That would, though, only give you five watts or so output. Unbalancing the sideband carrier might be more difficult, but would give you an easy 10-12 watts output. I achieved typically 10 watts output, brief tone, on SSB conversions.

The big problem with them is the PLL. Simply changing the reference oscillator just shifts the entire 40 channels upward. That's easy enough. But you are still channelized on 10 meters, and shifting the 40 channels up as far as the AM portion of 10 may require some circuit mods. When I did my mods, it was for the SSB portion of ten meters, which was easier.

In CB lingo, the "slider" was used to move between channels. If such a "slider" was installed, it could work just as well on 10 meters as it had on 11. It was, of course, easy to install one. This made a limited range VFO on both receive and transmit. But without rather delicate equipment, it can be hard to get that to track. I had an IFR Service Monitor, which made the job easy.

It would be easier to move the radio into the low end of 10, but that foregoes SSB or AM, and limits it to CW.

Good luck.

Ed

KB1IAI
10-25-2007, 11:59 PM
thanks for all the input. i was going to make it a beacon. its not like i dont have other radios, i do. i have a complete ft 101ee station and a heathkit sb102 complete station.
i really am into qrp, and thought this might make a good project. btw, i also have a uniden washington am/ssb cb.i was first licensed as a cber in the 60s before getting novice ticket in 70s. dropped out of radio for many years, and now back. built a pixie for 30. what a hoot when i made a contact with 100mw.my cw is terrible, but it will get better(i hope).
73 all
paul kb1iai

KC4UMO
10-26-2007, 12:07 AM
Quote[/b] (w2bbq @ Oct. 24 2007,14:43)]If I only still had that Uniden President Adams am/ssb with the digiscan box http://www.qrz.com/iB_html/non-cgi/emoticons/tounge.gif
I have one of those. "digiscan" units. It is on an old midland that has not worked in 20 plus years.

Paul,
sounds like a great project. I have an old 23 channel I converted many years ago.

K0CMH
10-26-2007, 01:10 PM
Go to the four state qrp group web site (google "four state qrp" and you will find their site). #On the home page, cursor down to about the bottom third of the page and find the link to converting CB to 10 meters becons.

It may not cover your model, but there is some good info there.

I find CBs in good operating condition, some like new, at garage and estate sales for $5.00 and $6.00.

N5CKC
10-26-2007, 04:30 PM
What all equipment is necessary when doing modifications on equipment like this. I am interested in learning to work on and with radios. Also what books would be good reading material to start with learning the basics. Thank you in advance.

W9GB
10-26-2007, 05:23 PM
Quote[/b] ]I have a cheap Citizens Band radio, that I would like to convert to ten meters.
Then, if possible, I would like to add CW to it.
My idea is to make DO, and not brand NEW.

Right atttitude.
Missing ingredient -- a bit more education and research (Internet is good place or your local library - both are free BTW). In other words, enough information to recognize gold from iron pyrite (fool's gold)!

Some models of Citizens Band radios were ideal for this type of conversion -- but NOT all models!
An earlier model by Hy-Gain was ideal and used models were quickly acquired by radio amateurs for that purpose.

A disadvantage of these CB conversions is that you are still "channelized" in frequency usage -- to either 23 or 40 channels.

Quote[/b] ]What all equipment is necessary when doing modifications on equipment like this. #I am interested in learning to work on and with radios. #Also what books would be good reading material to start with learning the basics.
START with your local technical/community colleges and vocational high schools -- some instructors are good Elmers for this field.
In addition to the basic courses -- in DC and AC (usual introductory courses) -- Practical BENCH TIME, is critical to becoming good in the field (if you are looking beyond just hobby/DIY). Understadning digital circuitry is becoming manadatory -- as traditional pure analog designs are rare.

w9gb

N5CKC
10-26-2007, 05:32 PM
W9GB, yea I am just looking for hobby, have no intentions of doing field work for others. I would be afraid I would damage their equipment, and the equipment isn't cheap these days. I would just like to tinker with mine and learn how to do it and be able to make my own repairs and modifications if needed. I will check into the local tech/comm college for the classes. Thank you again.

W9GB
10-26-2007, 05:35 PM
Quote[/b] ]have no intentions of doing field work for others. I would be afraid I would damage their equipment, and the equipment isn't cheap these days. I would just like to tinker with mine and learn how to do it and be able to make my own repairs and modifications if needed.
Building kits is the correct route for this type of learning. Heathkit, Knight-Kit and others filled this need several years ago.

Today, Elecraft is a good entrance (K1 or K2 radio) -- and you use the radio you have built.

w9gb

K0CMH
10-26-2007, 06:00 PM
ZZO:

The information on the "four state qrp" web site (the article by the fellow that converted a CB to a 10 meter becon) is a pretty good beginning on what can be required and what kind of parts, etc. it takes. It is not a "covers everything on the subject" but it can give you a good idea of what can be involved. It is a pretty quick read and does not get over techincal.

Good luck and hope this helps.

EDIT: I found the exact link. http://4sqrp.com/resource/10m_beacon/10m_beacon.htm

KA4DPO
10-26-2007, 07:41 PM
One of the easiest CB radios to convert to tem meters is the venerable Johnson White Face mobile. These can be had on Ebay for a few bucks and easily converted to operate 10 meter AM at 29.000 MHZ. CW can be added by keying the buffer.

WD4CHP
10-27-2007, 11:44 AM
I converted 2 Cobra 23 channel rigs for 29mhz am. I recrystaled them to get rid of the cb channel plan. I also modified the channel select switch to utilize the blank spot on the dial, thus giving me 24 channels. The only problems I ran into was that the output power was reduced and the channelization of the receive. I used a Radio Shack 1/4 wave cb ground plane antenna tuned for 29 mhz (no longer available).

By using the older crystalized rigs, you do not have to mess with the pll circuits.

Have fun.

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