I have a number Talking house transmitters, they range from TH 2 to TH 5. The TH 5 far surpasses the others in the series as far as audio quality. I have tested and tested and ran other TH 5 against other TH5s etc to make sure. The biggest problem is I cant come to a conclusion as to what the electronic differences are between the models. I can see there are several changes between the boards but with out a schmatic its almost hopless to figure out how to improve the audio performance of the older versions of the transmitters. I have tried eq's this does not have the same effect to create the audio of the TH5 . The audio of the TH5 has a sound that is full and easy sounding, the other models it seems as the audio bandwith is narrow and missing a lot of bass and some what restricted. They all work well but the audio is much closer to sounding like a broadcast station with the TH 5. Does anyone have any experience on modifing the earlier versions of the TH series to get better audio response? Schmatics are impossible to find,I know someone posted a link to the patent of a talking house transmitter but I need updated schmatics of the entire series of Talking house transmitters in order to make some progress. And a last note, does anyone know if TH has come out with someting past the TH 5? Thanks ,
Radio Joe
I recommend, if you are using a "certified" transmitter, you not make any modifications to the transmitter. If you do, the the unit is no longer under its certification and would be considered an experimental kit. There are no specific FCC rules I can point to to help you, but inspection case law is not in your favor.
The early models of Talking House transmitters were designed for "voice only" use. As such, the audio circuits have very limited bandpass (attenuated high and low frequency) and help process the audio for maximum intelligibility of the voice-range audio. Remember, the original Talking House units were used almost exclusively by real estate firms for open house tours.
Talking House was purchased by Radio Systems, Inc. and have redesigned the unit and its now called "iAM". The new iAM transmitters (based on the TH design) have an audio circuit more suited to transmission of music and other program material. Link to company: http://www.iamradio.net/index.php
Sometimes schematics for certified transmitters are available from the FCC Certification Data which is searchable based on the certification number on the unit. We've seen schematics for the C.Crane and Scosche FM transmitters by this method.
With schematics you could, at the very least, study the differences in audio circuitry.
And although changing the audio section is probably a technical voiding of the certification status, logic says that in a sensible world the objective of the certification is to control the RF output, and the changing of a few audio parts may not affect the RF performance. It would probably be a "fence sitter" where an inspector could judge either way.
Perhaps the new owners of the TH could help you with modification.
I got out my TH2, TH 4.3, TH 4.6 and TH 5 transmitters pulled the covers and my end thoughts on what I looked at was somebody went through a lot of unnecessary engineering on these transmitters. The auto tune circuit for the antenna is the best, but the rest of the transmitter as far as the "mess" they run the audio through is something else.
The TH 5 is the best made so far, so far as Talking House units are concerned, if any of you want a good AM broadcaster for around the home the TH 5 gives the best sound with the least components inside the box. The message part works good on all of the transmitters.
No schematics, no help from the company on technical issues dosent leave much for support.
These units are made in China some place and nothing else but the transmitter makes it to the states. I found some schematics on line but its outdated stuff, hard to read and all in pieces and the descriptions are hard to understand because they were written by people from another culture, which I don’t have a problem with but they are hard to relate to as to what they are trying to say.
It wont hurt if the people selling these transmitters would make available a great service manual written for technical people. So because of the lack of the above, I just gave up, Im done bridging caps all over the place to try to find a fix to crappy audio on the early versions of Talking house transmitters. Good luck on trying to figure out the audio path. ( or the rf path)
Easy way out is to sell off your older TH broadcasters, and find a TH 5 on eBay for the best price you can get. End of your bad audio on the early TH series.
I got out my TH2, TH 4.3, TH 4.6 and TH 5 transmitters pulled the covers and my end thoughts on what I looked at was somebody went through a lot of unnecessary engineering on these transmitters. The auto tune circuit for the antenna is the best, but the rest of the transmitter as far as the "mess" they run the audio through is something else.
The TH 5 is the best made so far, so far as Talking House units are concerned, if any of you want a good AM broadcaster for around the home the TH 5 gives the best sound with the least components inside the box. The message part works good on all of the transmitters.
No schematics, no help from the company on technical issues dosent leave much for support.
These units are made in China some place and nothing else but the transmitter makes it to the states. I found some schematics on line but its outdated stuff, hard to read and all in pieces and the descriptions are hard to understand because they were written by people from another culture, which I don’t have a problem with but they are hard to relate to as to what they are trying to say.
It wont hurt if the people selling these transmitters would make available a great service manual written for technical people. So because of the lack of the above, I just gave up, Im done bridging caps all over the place to try to find a fix to crappy audio on the early versions of Talking house transmitters. Good luck on trying to figure out the audio path. ( or the rf path)
Easy way out is to sell off your older TH broadcasters, and find a TH 5 on eBay for the best price you can get. End of your bad audio on the early TH series.
I ordered direct from the factory as they had a deal I could not refuse. 99 bucks makes this a very affordable unit. Could wait for one on eBay but now I have a year warranty. Would never pay 200 or more for a lpam unit. I hope this unit preforms as well as my other one did.
I ordered direct from the factory as they had a deal I could not refuse. 99 bucks makes this a very affordable unit. Could wait for one on eBay but now I have a year warranty. Would never pay 200 or more for a lpam unit. I hope this unit preforms as well as my other one did.