- September 25, 2019 at 2:19 pm #112976
Need top and bottom detailing components and traces. I’m trying to restore some rev. D and F rangemasters to stock. the ones i have someone modded the shit out of them and they are throwing harmonics and spurs all over the place.
I need high res pictures of top and bottom of Rev. D & F units, specifically detailing stuff like resister color coding, etc.
- September 26, 2019 at 4:38 am #112981
Why not contact Keith directly?
- September 26, 2019 at 8:12 am #112983
Total posts : 261
No link to prove this one but I’ve heard from a friend he is VERY VERY hard to get a hold of and he absolutely will not disclose ANY schematics for the Rangemaster. Progressive Concepts also sells the Rangemaster transmitters you might get something from them.
This may sound silly but to get certified by the FCC often if you look there are pictures of the main motherboard but schematics may be another thing.
Sad to say this but I’m afraid your gonna be forced into purchasing a New transmitter because Keith is not going to allow (with his knowledge) any schematics of his transmitter.
- September 26, 2019 at 12:19 pm #112986
Total posts : 398
It usually takes over an hour for him to respond to an email. Sometimes as long as three hours. Just be patient, take a nap or something.
- September 26, 2019 at 6:54 pm #112990
keith got back to me. he didn’t have any board pics so i need to locate some pics still.
- September 27, 2019 at 9:20 am #112992
i got a top picture of a Rev. F unit need a bottom pic of a Rev. F unit.
- September 27, 2019 at 4:34 pm #112996
TheLegacy wrote” No link to prove this one but I’ve heard from a friend he is VERY VERY hard to get a hold of…”
I have found the opposite to be the case and , in once case, have talked to Keith via telephone. You should rely less on “friends” information and more on your own experience rather than conjecture.
He also wrote “…because Keith is not going to allow (with his knowledge) any schematics of his transmitter.” You are speaking for Keith and I fail to understand how you can do this. It may well be that Keith wants to restrict such information but unless he so states it is not appropriate to ascribe such motives to him.
The most useful comments you can offer are those based on your own direct experience and not those of “friends” or your own supposition. As was well stated earlier in this thread “Why not contact Keith directly?” is good advice.
- September 28, 2019 at 7:54 am #113001
I got schematics and a board layout from him (had to sign an NDA so i can’t give them out) but the schematic lacks part location references such a T1, R4, Etc.
this is why i need the pics of a Rev. F board. i got the top of the board and have been fixing the board based on what i have already but i need a hi res pic of the bottom to see what should and should not be there.
between schematics and pics of a stock board layout i should be able to fix these transmitters i have back to stock.
someone got into these with their golden screwdriver and really monkeyed them up, i have a long job ahead of me even with schematics and pics to restore all three back to stock.
- September 28, 2019 at 10:38 am #113003
Total posts : 481
Honestly, I don’t think from even a high resolution picture you can accurately see the exact color codes on resisters, coils, etc and even capacitor values. You will mistake red from brown, violet from blue, etc., as an electronic recreation is not like your eyes.
How did you happen to get these that were screwed up this badly? I for one would never buy something someone else has screwed up, modified, etc. especially an expensive transmitter like this.
I really would help if I could but I don’t have one to remove the board to take pictures of top and bottom. I think Keith is your best bet if you explain the problem and he, and I can’t speak for him, MAY send you what you want or you can ask if he will do the repair at a reasonable cost.
- This reply was modified 2 weeks, 3 days ago by Mark.
- September 28, 2019 at 3:26 pm #113006
Part15Engineer wrote “I got schematics and a board layout from him (had to sign an NDA so i can’t give them out) but the schematic lacks part location references such a T1, R4, Etc.”
Help me understand your situation. How would pictures of the board help you if you have the actual board in front of you? It seems that having the pictures would offer no more information about parts locations than you already have.
It seems that the schematic lacks specific parts designations which is very unusual. If this is the case then you will need to do a bit of “reverse engineering” and identify how the components are placed and connected. This is usually pretty easy if you have the schematic.
I am trying to be helpful and to do so I need to understand what information you lack.
- September 29, 2019 at 1:51 am #113007
a pic of a stock board (remember mine is not stock) would help in tandem with the schematic as a confirmation of what belongs where. between the two using the board pics as a guide and schematic as a confirmation of what belongs where would go a long way to helping me fix the issues here. i have already begun to correct the topside using this method.
it’s a quick visual aid backed up by a scheamatic.
and i am not currently in a financial position to just pay Keith an open ended hourly rate to repair the units.
- September 29, 2019 at 3:05 pm #113014
At first I missed that your board has been modified and it does make sense to get pics of a good board to undo the damage.
Hope someone can provide this for you.
- September 30, 2019 at 8:17 am #113015
Total posts : 261
After so much damage you have to wonder of buying a whole new Rangemaster transmitter may be your best choice. You can’t risk putting something on air that may be damaged to the point where you will be spewing out harmful spurs which unless you have a spectrum analyzer you really can’t tell. Look at my situation with a faulty FM transmitter I had spewing out spurs and wiping out frequencies in the spectrum. Its an easy way to get a unwanted visit from the FCC and depending how much harm you caused they may not just stop at a NOUO letter they may stick you with a NAL and that is not really worth the risk.
We as hobby broadcasters have a responsibility to not look bad in the eyes of the Public, NAB, FCC and there is enough bad apples doing so without much care. This could also work against some of us who are trying to fight for more power on the Dying AM Broadcast Band for Hobby and community use.
If you have a spectrum analyzer, Watt Meater, or FIM then of course you can do tests using a dummy load to avoid any real world interference issues.
Good Luck let us know the outcome.
- October 1, 2019 at 4:02 am #113020
Hi TheLegacy. I looked online for a watt meater but no suksess. Can you point me to it?
- September 30, 2019 at 5:20 pm #113017
- October 1, 2019 at 8:34 am #113021
Total posts : 87
If the previous owner of these units was the one who did the mods, it may be possible he/she still has schematics or photos available. I’d give them a ringy-dingy.
In the absence of a decent spectrum analyzer, an inexpensive garden-variety SDR that covers 300 kHz-30 MHz will do well to sniff out spurs. But if you can’t undo the mods done by the previous owner, you may need to fabricate a steep low-pass filter to attenuate whatever harmonics you discover, and call it a day.
Be aware that patching a patch will mean it is no longer FCC type-accepted. Proceed with all due caution.
- October 7, 2019 at 3:06 am #113028
i now have hi res pics and schematics and parts are on order and will be here today. i’m good to go on arrival of parts.
- October 7, 2019 at 5:11 am #113029
Billy said: “Be aware that patching a patch will mean it is no longer FCC type-accepted. Proceed with all due caution.”
I said: That’s not entirely true. Any modification to the RF circuitry would require a “permissive change.” Repair would not.
- October 8, 2019 at 3:40 am #113032
Total posts : 87
AMRL – True that restoration to the original circuitry would probably retain type acceptance. But installing a filter to eliminate spurs created by the mods (a “patch to a patch”) drastically alters the design enough to put certification in jeopardy.
If The Man With The Payin’ Paper shows up, we got some ‘splainin’ to do.
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